L1 SenseMon in Science Segments

I calculated the median SenseMon range in each L1 science segment in S5, and the standard deviation of each segment longer than 2048 seconds. The standard deviation is a rough measure of "glitchiness", with the histogram showing a long tail. I ranked the segments according to their standard deviation, and investigated reasons for the large stand rd deviation reading the elog, especially entries by operators and scimons. I suggest DQ flags for the segments investigated and sometimes other times, arising from the investigations.

This is a follow up on on a similar investigation on the first year of L1, so the ranking here contains segments investigated earlier, but in a different ranking position. The DQ flags suggested for the first year are comments in red, the new suggestions are in magenta.

Range median and std in science segments	Histogram of median range in science segments
Range daily median and std	Histogram of range standard deviation in science segments

S5 Glitchy segments: ranked list

List of Science Segments longer than 2048 seconds, ranked by standard deviation in decreasing order.

#	SenseMon	GPS Start - End	Range Mean, Std	Start UTC	Comments
1		828531745-828536366	7.1+/-3.6	Apr 08 2006 11:42:11 UTC	This segment is taken during a commissioning period. After a storm, a lot of glitchiness and saturations. The previous segment is #22 in this table, with a 2.3 Mpc std. The segment is ended by the operator when the range drops to a steady 0.5 Mpc. The ordeal ends for Tuesday maintenance, and a few days without data follow for commissioning. Rana says the next day: "Found that yesterday's glitching problem was indeed mis-alignment on the PD as Harry said. The misalignment gave us a large offset in AS1_Q." There are many inspiral triggers with SNR>8 and up to SNR~2,000, starting at 828523656. If we cluster these triggers with a 10s window, we veto most of them with ASI_CORR LSC overflow flags, but there are a few left, including the first at 828523656, with SNR 11, with no DQ flag nearby. The minute that follows this trigger is the first minute when the SenseMon range falls to 10 Mpc. The KW rate for triggers with significance larger than 50 is in 5% top percentile for the 6 hr interval containing these segments; see day 154.7 in this plot from Laura's page, also visible as a spike in KW rate before the commissioning break in the L1 Epochs plot, near day 155. I suggest a DQ flag starting at 828523656, until the end of the segment plotted, at 828536365.
2		841278773-841282367	12.7+/-3.3	Sep 03 2006 00:32:39 UTC	This and Rank#4, 5 are some of the September "high power glitchy times"; the afternoon operator's log mentions problems when increasing the power at night, starting with segment #2994 at 841277924 (a short segment not in this list), until the end of segment L1-2999, 841291321, when the operator lowers the power due to glitchiness. The much cleaner segment that follows the end of Rank#5, also with higher range, is clear in the plot. The clean segment (#3000) ends an hour later due to an earthquake. There are many inpiral triggers generated at the noisy times with SNR up to 1,000; most of the loud ones are vetoed by overflow DQ flags, but there are still many left with SNR>10 that are not vetoed. This is one of the first days of the "noisy September" epoch. This day is in the top 1% percentile of KW rates. I suggest a DQ flag for segs with high power at this time, between 841277924 and 841291321.
3		874374723-874379838	14.7+/-3.1	Sep 21 2007 01:51:49 UTC	This seg L1-6313; Related: #63=L1-6312, #50=L1-6315; also rank#38=L1-6323 (last one affected). Several segments, beginning with L1-6312, end badly apparently due an oscillation at 3.6 Hz, ending with 6323, which was really badly affected in the middle. It was later discovered to be a BS op lev servo with too much gain, and was fixed at ~21 UTC (end of L1-6323). Segments 6316-6318 are not obviously affected (but they may be?). Suggest a BS OPLEV DQ flag for segs 6312-61323, GPS 874369184 - 874443314 Note: elog on Sep 08 mentions a similar oscillation: maybe a follow up is needed.
4		841282615-841288956	12.6+/-3.0	Sep 03 2006 01:36:41 UTC	See Rank#2.
5		841289008-841291320	13.1+/-2.9	Sep 03 2006 03:23:14 UTC	See Rank#2.
6		840969500-840971605	13.7+/-2.9	Aug 30 2006 10:38:06 UTC	The large standard deviation is due to this being a short segment which ends with a train. There is a L1:TRAIN_LIKELY:v3 flag ACTIVE (840971130-840971606), and several OVERFLOW flags active in the last few seconds of the segment. I don't think any other flag is needed in this segment.
7		837466229-837468625	11.0+/-2.9	Jul 20 2006 21:30:15 UTC	This is the last and worst of several consecutive bad segments, two in this list: #84, (starts 18:20, std=1.7 Mpc), #122, (starts 19:24, std=1.6 Mpc).  SciMon (Joe Giaime) reports: "Several strong thunder storms passed through this afternoon, complete with very heavy rain and gusty wind, causing several hours of poor sensitivity and frequent AS trips & lock losses. There have also been repeated episodes of the low-frequency excess bumps mentioned above (but not yet understood)." This particularly noisy segment seems to correspond to the peak of the storm, as seen in the 0.03-0.1Hz band in FOM5. There are many inspiral triggers in these segments, some very loud; although the loudest ones in the previous segments are vetoed by OVERFLOW flags, most of the ones in the stormy segment are not vetoed. The rate of KW triggers this day are in the top 5%: see day 258 in the L1 Epochs page. There is a sharp transition in the middle of segment L1-542 (837454853 - 837458600, #47 in this table), at 837456840, t=-2.5 in this segment's plot, when the range first drops for a minute to 6.6 Mpc. That is also the time when the rate of SNR>10 inspiral triggers rises sharply. I suggest a DQ flag starting at 837456840, and ending at 837468626 (the end of the segment plotted).
8		840618156-840623169	13.6+/-2.9	Aug 26 2006 09:02:22 UTC	Another glitchy segments follows this one (#77 in this list, starts 12:31, std 1.7 Mpc). This is again a segment with high power and increased glitchiness. Operator's note (D Hoak): "We had a crummy night: ASI was growing through the locks and causing lots of glitchiness. I fiddled with the TCS a bit this morning and hopefully found a happier place". SciMon note (Chiadini): "Rough nightshift, IFO has been very glitchy. " All (!) of the SNR>10 inspiral 10sec clusters in the bad times of these two segments are vetoed by OVERFLOW flags. The KW rates are not particularly high, as seen in the L1 Epochs page (this segment is in day 295). In fact, ASI CORR overflow flags 12% of this segment, some at the beginning (while detector is warming up), but most after 840619181. 50% of these ASICORR overflows happen less than 4 seconds apart. The noisy times derived from SenseMon are 840620280-840623170 in this segment, all of the next (short) segments, 840624759-840625717, 840625868-840626427, 840626560-840627349, and 840632580-840635295 (end of the next long segment).
9		863961233-863963328	13.7+/-2.8	May 23 2007 13:13:39 UTC	This is the worst segment affected in what was three weeks of logging very close to the X-end; see photos here and here. Many entries recommend flagging the segments affected during logging (which happens Mon-Sat, ~11:30-21:00 UTC, except for rain and holidays). The logging started on Tue May 22, but since it was maintenance day it only affected a few segments at the end of the day that day, and the problem was only recognized on Wed May 23. Logging in that area ends on Mon June 11, although that last day the seismic noise was much smaller and did not affect the range (probably they were just wrapping up). While there is logging, SenseMon shows a smaller mean, larger fluctuations, and often serious glitches. Going through the elogs, the FOM1 plots, and the list of science segments, I recommend an "EX-logging" DQ flag for the following times: Wed May 23: 863955675 - 863988908 Thu May 24: 864043095 - 864077024 Fri May 25: 864127648 - 864163634 Sat May 26: 864214750 - 864244554 (no logging on Sunday or on Memorial Day) Tue  May 29: 864476223 - 864501980 Wed May 30: 864560801 - 864593047 Thu May 31: 864163630 - 864652520 (logging ends early due to rain) Fri June 1: 864735567 - 864767453 (no logging Sat, Sun; rain on Monday) Tue June 5: 865079160 - 865105539 Wed June 6: 865164614 - 865198779 Thu June 7: 865258214 - 865282769 Fri June 8: 865335614 - 865365713 Sat June 9: 865422014 - 865454714 (no logging Sun, smaller noise on last day on Mon).
10		864214750-864217016	14.1+/-2.7	May 26 2007 11:38:56 UTC	EX logging: See above, rank #9.
11		835610669-835615175	13.3+/-2.7	Jun 29 2006 10:04:15 UTC	The large standard deviation is mostly due to the end of the segment, while riding a train: L1:TRAIN_LIKELY:v3 ACTIVE (835614390-835615175). The earlier single minute drops in SenseMon do not have any DQ flag nearby, nor are noted in the elog. I don't think this segment needs any other DQ flag.
12		841184921-841188952	11.8+/-2.6	Sep 01 2006 22:28:27 UTC	Several segments in the plot are in the list with std>=1Mpc: the earlier one, starting at 21:04, is #104, with std=1.6 Mpc; the one that follows, starting at 23:49, is #69 with std=1.8 Mpc. Microseismic noise is very large, the storm "Ernesto" was arriving to the Atlantic shore this day. Detector runs with "daytime power" even at night to preserve lock. The non stationary high noise is responsible for the scatter of the points, but the large range drops are more serious consequences, probably overflows. Dan Hoak says: "The spectrum is very nonstationary, and the excess noise is VERY broadband. It doesn't look like the typical upconversion - instead, the whole spectrum will breathe with a period close to that of the microseism. ASI and SPOB are very noisy.". Suggest an "Ernesto" DQ flag, Segments L1-2977-2985.
13		863980433-863982725	13.0+/-2.6	May 23 2007 18:33:39 UTC	EX logging: See rank #9.
14		838945244-838947647	11.7+/-2.6	Aug 07 2006 00:20:30 UTC	Operator's (J. Hanson) notes earlier problems with MC WFS, and about this segment: "0020 Locked SM; 0100 Took out of SM because of glitching; 0104 Valera turned down the WF1 gain; 0105 Back in SM". Mike Zucker's note about this time: "Two large peaks, at 31 and 34 Hz, appeared shortly after the IFO warmed up, degrading range and eventually overloading DARM. JH pulled out of science mode. Valera found it was WFS1 pitch oscillating and reduced both pitch and yaw gains; oscillation disappeared. " Many inspiral triggers generated at this noisy time, all but one 10s clusters are vetoed by ASC overflow DQ flag. I think we should define a flag for the time between 838946880 and 838947647, due to the recognized problem in WFS1.
15		825700595-825705734	9.2+/-2.6	Mar 06 2006 17:16:21 UTC	Dan Hoak about this bad time: "We had a slowly worsening noise spectrum over a period of about thirty minutes today. Attached is a DARM spectrum during the period; the slope of the noise is close to 1/f. There were no overflows; I checked the OpLevs, QPDs, and the gold-plated conlog for bad news. The only hint of trouble was in the WFS; there was a lot of coherence between DARM and WFS1 pitch (the second page in attached document). The IFO lost lock before we could really dig our diagnostic teeth into the problem; when we returned to power-up the noise curve was back to normal." Same WFS1 problem as #14 on Aug 07? A DQ flag should be defined between  825703200-825705734.
16		816750805-816752853	4.7+/-2.6	Nov 23 2005 03:13:12 UTC	The problem start with the previous segment, #108 in this list, starting Nov 22 23:37, with std=1.6 Mpc. Operator J. Hanson notes: "2329 Locked SM; 0052 Train; 0250 Broke we were having large glitches for the last 40 min or so; 0312 Locked SM; 0347 Broke the large glitches came back?" Ken Franzen scimon's notes describe the same problems, but also notes they were solved when a TCS script was run (the next segment is clean). There should be a DQ flag defined between 816742980-816752854
17		820077106-820093611	10.0+/-2.5	Dec 31 2005 15:11:33 UTC	A time inadvertently running on AS5; there is a DQ flag covering this already.
18		864728247-864742164	14.5+/-2.4	Jun 01 2007 10:17:13 UTC	EX logging: See above, rank #9. Logging starts in the middle in this segment, it's obvious the bad effect it has...
19		871652611-871656473	9.5+/-2.4	Aug 20 2007 13:43:17 UTC	Earthquake: 11:30 UTC - 17:00 UTC. Earthquake DQ flag 871644614-871664414.
20		865005208-865008323	13.1+/-2.4	Jun 04 2007 15:13:14 UTC	Dan Hoak recommends flagging these segments: " The y-axis seismic noise around the corner station has given us a rough ride this morning. Segments 5459, 5460, and 5461 should be flagged as unlovely." This is *not* the logging at the X-end, which did not happen this Monday due to rain. The times for the segments mentioned are 864999206 - 865010998.
21		841305348-841316100	13.4+/-2.3	Sep 03 2006 07:55:34 UTC	Dan: "An earthquake in Panama reduced the sensitivity just before it activated the AS trigger." The previous segment ends with a dip due to a train, and the segment before that one (the cleaner one starting at t=-6) ends with a dip due to another large EQ. I suggest EQ flags for GPS 841313714-841316101 (end of this segment) and GPS 841295414-841296222 (for the earlier one).
22		828518267-828528803	10.3+/-2.3	Apr 08 2006 07:57:33 UTC	See Rank#1.
23		831569461-831572000	13.0+/-2.3	May 13 2006 15:30:47 UTC	Not clear what the problem is; operator (H. Overmier) notes "Large spikes in the STS-LVEA STS2_X_1-3Hz" as possible suspects for the loss of lock at the end of this segment (it is Saturday). There is also some wind, blamed for the previous lock loss. The next segment has a lower range because the power is lowered to allow for locking and low noise mode. Not obvious DQ flag needed (this was the conclusion n the 1st year page). On a second look, it seems that the 1-3Hz seismic noise in the LVEA has a noticeable effect in the SenseMon stationarity, as seen when it starts (beginning of this segment) and more evidently when it ends (21:30 UTC). I suggest an X-LVEA Seismic DQ flag: 831569461-831591014.
24		859827065-859831295	12.4+/-2.3	Apr 05 2007 16:50:51 UTC	Train DQ flag applies to the second part of this segment: 859830630 859832130 (17:50-18:15 UTC). Scimon (M. Zucker) says: "Shift started out rocky, evidently due to combination of Y end anthropogenic noise and moderately high winds." (shift begins with this segment). Low freq noise increases at ~14:00 UTC (shortly before another train that breaks lock of a longer segment). We should flag the segments with a "glitchy for unknown reason" DQ flag, for segments L1-4898 to 4901, or GPS 859822359 - 859831295
25		874311276-874314559	14.8+/-2.2	Sep 20 2007 08:14:22 UTC	Earthquake, 8:45-13:00 UTC, or 874313114 - 874328414. The next segment does not seem affected (probably because it's also using lower power), so I propose an earthquake DQ flag for the end of this segment, 874313114 - 874314559.
26		841110269-841113984	12.4+/-2.2	Sep 01 2006 01:44:15 UTC	After a long hiatus due to 1-3 Hz daytime seismic noise and some trouble with a cold Faraday isolator, the detector started up at 22:16 (seg 2961), but it was in a "glitchy" state. Power was increased from 6W to 7W at 00:29, but it was set back to 6W for the segment highlighted here, due to glitchiness. It got better after Brian changed some WFS gain, at 5:00 UTC.The larger scatter in this segment compared to previous days is due to the increasing microseismic noise (the tropical storm Ernesto arrives a day later, see #9 above). I suggest a WFS DQ flag for segments 2961-2971.
27		825748576-825751665	10.3+/-2.2	Mar 07 2006 06:36:02 UTC	An earthquake that starts at ~6:00 ends seg#1155. While we wait for a true EQ flag, I suggest a preliminary EQ flag for GPS 825746414-825751666.
28		872284766-872287802	14.2+/-2.2	Aug 27 2007 21:19:12 UTC	Wind added to normal daytime 1-3 Hz noise makes this segment, and previous two short ones, noisy. Wind DQ flag: 872282956 - 872287802 Also, there's an earthquake visible in an earlier segment, 17-19 UTC. EQ DQ flag: 872269214 - 872276414.
29		842050745-842054683	13.5+/-2.2	Sep 11 2006 22:58:51 UTC	Dan: "Glitches caused by a combination of high-power operations and elevated microseism. This was shortly after the August 06 commissioning break, when we were trying to push the envelope a bit." The first dip in range at ~19:00 (not in the highlighted segment) is a small earthquake (2.7 in Alaska), followed by a train. The second dip at ~22:00 is another earthquake (2.8 in Southern CA). At 22:24, after the EQ,the power is increased, and the highlighted segment L1-3082. After power is increased, the scatter in range is larger, and there are glitches. Mike Z. (scimon): Since Doug went to night power about 7h ago the statistical FOM's have looked ratty. BurstMon pixel fraction went from 0.2 to 0.35 with fluctuations above .5, the online BNS search has numerous outliers above SNR=10, PulsarMon crabbytime went up a factor of two, etc. In addition we are seeing excursions of ASI_CORR to +/- 20,000 counts and occasional 30% dips in SPOB. [...]After an AS trigger at GPS 842074652 I asked Tom to roll back down to day power. Segment 3084 is at 5.6W." After the power is decreased, the scatter is smaller and most of the glitchiness disappeared. I suggest a DQ flag for segs L1-3082-3083, *and* an EQ flag for GPS 842034614-842038684 and 842045414-842048738.
30		816776926-816783835	9.0+/-2.2	Nov 23 2005 10:28:33 UTC	Dan: "Beginning-of-run glitches. They were noted, but not explained, in the elog.". I suggest a DQ flag for the whole segment, 816776927 - 816783836.
31		873084495-873086592	15.0+/-2.1	Sep 06 2007 03:28:01 UTC	Last 15' of segment affected by an EQ at 3:42 UTC, suggest an EQ DQ flag 3:42-4:03 UTC, or GPS 873085334 - 873086592.
32		872876709-872880787	14.9+/-2.1	Sep 03 2007 17:44:55 UTC	EQ: 16:30-18:30 UTC, 872872214-872879414
33		872427700-872431917	12.7+/-2.1	Aug 29 2007 13:01:26 UTC	Heavy logging near the corner station, also visible the next day, produces the very noticeable drop in range. Dan's elog on the next day (Aug 30): "There's logging behind the SEC that's causing a lot of seismic noise near the corner station. All the data during logging hours today (7am-5pm) [12:00-22:00 UTC] should be flagged as noisy." LVEA-Z Seismic noise (logging) starts on Aug 31 at ~12:00 UTC, but stops early at ~14:30 UTC. Also Rank#44 (starting at 12:14) is on Aug 29. I suggest an "SEC logging" DQ flag on: Aug 29 12:00-22:00 UTC, GPS 872424014 - 872460014 Aug 30 12:00-22:00 UTC, GPS 872510414 - 872546414 Aug 31 12:00-14:30 UTC, GPS 872596814 - 872605814
34		840201913-840205589	13.6+/-2.1	Aug 21 2006 13:24:59 UTC	Dan: "I think RBS saturated at the very end of the lock, making the IFO a little noisy for a few minutes. This was shortly after the new PMC was installed to increase the power into the IFO, and we hadn't yet adjusted our compensation loops." I suggest a (RBS?) DQ flag for GPS 840204314-840205590 (21 minutes at the end of the segment) From minute trends, the interval with a railed RBS PZT is 840204720-84020590. No other times with gps 840* are found with a railed PZT.
35		872638550-872643181	15.2+/-2.1	Aug 31 2007 23:35:36 UTC	The segments during the owl shift ending on Aug 31 13:00 UTC had problems with a dead RBS PZT. From minute trends, the problem starts on Aug 31 2:45 UTC, problem was fixed replacing the mirror PZT at 23:15 UTC. However, the PZT dynamic range seemed to be limited for running at high power, and this segment and the previous one apparently suffered from this. Joe Hanson's op log: "2336 Back in SM   0053 Broke lock, I had just called Valera because the noise and range has suddenly tanked.    0116 Locked SM, we are now running at 7 watts do to the range of the RBS picos" Later on, the WFS were recentered and the problem was apparently solved: '"0214 Removed from SM to adjust WFS 0224 Raised power back to 8 watts 0229 Back in SM" Overall, from minute trends of mirrors' "out16" control signals, we found only two intervals when the control was railed: (end of this segment, L1-6138): 872642640-872643240 (end of earlier segment, L1-6126): 872579160-872580780. This last segment is also identified by the operator elog: "0732 IFO lost lock, RBS M2 yaw railed for some reason, clearing history and pre heating." These are the only times with gps times 872* when a mirror's PZT was railed.
36		836831802-836834883	12.4+/-2.1	Jul 13 2006 13:16:28 UTC	Dan: "Segment ends due to a train. This was shortly after the SPOB PenTek failure. The ongoing efforts to debug that problem caused some minor trouble with WFS1, which led to elevated ASI during this segment." Segment L1-2445 ended suddenly with a lock loss on July 12 20:37, and there was a large offset in SPOB afterwards that made locking difficult. A work-around was found, but the problem was tracked down on July 18 to SPOB's Pentek. Segment L1-2507 is the first one without an SPOB offset. This particular segment has a problem with WFS and ASI, and they are associated with ASI-CORR overflows; I don't think there is enough evidence for another DQ flag (since overflows have a DQ already). However... I think we should have a DQ flag for the whole time the detector was running with a malfunctioning Pentek, for segments L1-2446-2506.
37		841574733-841577640	14.1+/-2.1	Sep 06 2006 10:45:19 UTC	A train arrives at the end of this segment, there is a train DQ flag: 841577130 841578090. Nothing else needed here.
38		874436696-874443314	12.9+/-2.1	Sep 21 2007 19:04:42 UTC	See Rank #3. Last segment affected by BS problem. Ops log: "1905 The trigger has been reset and the IFO is back in Science Mode. This is segment S5-06323. 2055 We are experiencing 3.6 cps oscillations, and have dropped out of Science Mode so Valera can run some measurements." Valera's elog entry: "We found that the BS oplev servo was gain peaking at 3.6 Hz in the low noise. The reason for that was the digital compensation of the dewhitening gain. It is off by ~2 dB with dewhitening on. We set the BS oplev pitch and yaw ugfs in run state with dewhitening on."
39		825537371-825541189	10.3+/-2.1	Mar 04 2006 19:55:57 UTC	Dan: "From the scimon's report on this segment: "About 20 minutes into the segment, there were a couple of big glitches, and about 15 minutes later, it got really glitchy, same as yesterday; the segment ended with an AS trigger, and the next (short) segment ended with lock loss.... Most (but not all) the glitches produced LSC overflows in ASQ1-4, but not in ASI or ASI_CORR or ASC." ". I suggest a "glitchy for unknown reason" DQ flag for this segment.
40		859308217-859313677	13.4+/-2.1	Mar 30 2007 16:43:23 UTC	Glitchy segment due to wind. Suggest "windy" DQ flag for all of this segment, 859308217-859313677. Also, EQ in segment that follows: A 5.1 earthquake in Guerrero, MX, at 19:00:45 (UTC). EQ DQ flag 19:00-21:00 UTC, 859316414-859323614.
41		837584168-837587647	14.0+/-2.0	Jul 22 2006 06:15:54 UTC	A train, already with DQ flag including the last 5 minutes of this segment: 837587310 - 837587647.
42		825240303-825247839	10.0+/-2.0	Mar 01 2006 09:24:49 UTC	Dan: "No clear cause for glitches. The microseism was high, but the glitches began (and ended) spontaneously". The preceding segment is #98 in this list. I suggest a "glitchy for unknown reason" for ~t=-4.5 to t=-0.5 in this plot, or 6:00-10:00 UTC = GPS 825228014-825242414.
43		841114112-841116223	12.5+/-2.0	Sep 01 2006 02:48:18 UTC	See Rank #26.
44		872424889-872427631	13.8+/-2.0	Aug 29 2007 12:14:35 UTC	See Rank#33.
45		840530007-840540256	14.1+/-2.0	Aug 25 2006 08:33:13 UTC	Dan: "Segment ended by logging. There was no clear explanation for deep glitches before the seismic noise increased." There are 186 different ASI-CORR or SEVERE-LSC overflows in this segment; there are overflows in all the minutes after 11:15 (the segment ends at 11:24). It is not obvious we need another DQ flag...
46		834292021-834295173	13.0+/-2.0	Jun 14 2006 03:46:47 UTC	Earthquake, 6.8, Aleutians. I suggest an EQ DQ flag, GPS 834294314-834295173
47		845327352-845330332	12.3+/-2.0	Oct 19 2006 21:08:58 UTC	Dan: "The glitches at the end of this short segment are due to an approaching train. Also, the IFO was warming up, and the microseism was elevated." The glitches in the warm-up time are not associated with ASI_CORR or SEVERE-LSC overflow flags, except for one. I suggest a glitchy warm up DQ flag for the first 20 min of this segment: 845327353-845328553
48		861379694-861381787	14.2+/-2.0	Apr 23 2007 16:08:00 UTC	The power was increased from 7W to 8 W for this segment, as seen in FOM1. Wind and high power running made segments 5051-5053 short and very glitchy, so the power was decreased to 7W again at 17:35 UTC. I suggest a "wind+high power" DQ flag for these segments, 861379694-861384914.
49		844596993-844599960	13.0+/-1.9	Oct 11 2006 10:16:19 UTC	There's a train at the end of the segment, with train DQ flag: 844599570-844599960.
50		874385837-874395597	14.4+/-1.9	Sep 21 2007 04:57:03 UTC	See Rank#3.
51		869304912-869313990	13.3+/-1.9	Jul 24 2007 09:34:58 UTC	The large standard deviation is probably due to the warm up at the beginning, which should not be a problem (except for its rapidly changing sensitivity). The last minute has several overflow flags. There is a PHOTODIODE_GLITCH flag, 869312580 869312640, for the lowest point of the cluster of minutes with low range; there is no flag for the single minute drop, though. Not enough evidence for a glitchy segment flag in here.
52		817207370-817212020	7.5+/-1.9	Nov 28 2005 10:02:37 UTC	Dan about #86 (the segment that follows this one): "An ugly segment ended by a train. There were ongoing problems with HEPI for ITMX (it turned out to be a broken PenTek)". I suggest a "glitchy for unknown reason" for both of these segments, or 817207370-817218064.
53		816663558-816665700	9.1+/-1.9	Nov 22 2005 02:59:05 UTC	The large drop and the last minute have SEVERE_LSC_OVERFLOW flags, no other DQ flag needed.
54		865786567-865792020	13.6+/-1.9	Jun 13 2007 16:15:53 UTC	There's an SEVERE_LSC_OVERFLOW near the first large range drop; there's an INJECTION flag at the beginning of the cluster of large drops near the end of the segment; there's also a PD_OVERFLOW flag for the last second. The detector range changes in the last ~15' of the segment due to seismic noise at the Y-end; however I don't think there's enough glitchiness or evidence for a flag.
55		862241366-862248881	13.9+/-1.9	May 03 2007 15:29:12 UTC	Two earthquakes, ther first one affecting the end of the previous segment,  produces a  lock loss, and then to a less extent affects the beginning of this segment. The second EQ, a shorter one, affects the end of this segment. The two EQs overlap, so I suggest an EQ flag from 13:56 (beginning of first EQ) to the end of this segment: 862235774-862248881
56		849270202-849274970	10.6+/-1.9	Dec 04 2006 12:23:08 UTC	Logging near the X-end... the logging begins on this day (Mon Dec 4), and affects segments at the beginning of the day (L1-3869,70) and at the end of the daytime (L1-3871). No locking was possible during the day due to the logging. Although there was logging the rest of the week, segments were not affected as much (when detector was locked), b/c operators used a lower input power. X-logging DQ flag: 849269301-849306494.
57		872598378-872600503	12.1+/-1.9	Aug 31 2007 12:26:04 UTC	Seismic noise in the corner station affects the noise, starting with the end of the previous segment, and affecting also the next couple of segments. The first minute to have a significant range drop is 11:52 UTC, in L1-6130. Segments affected afterwards are l1-6131, 32, 33. Suggest an "LVEA seismic DQ flag", 872596380-872603817
58		837794403-837798840	13.0+/-1.9	Jul 24 2006 16:39:49 UTC	A thunderstorm affects a fraction of this segment. Storm DQ flag: 837796253-837798003.
59		823328764-823333867	8.3+/-1.9	Feb 07 2006 06:25:50 UTC	Dan: "Microseism, noted in ops log". I suggest a "glitchy for unknown reason" for this segment.
60		834431503-834436995	12.0+/-1.9	Jun 15 2006 18:31:29 UTC	Dan: "Small earthquake, small train". EQ (at t=-2) affects the beginning of the segment; train at end is flagged and does not affect the range much. EQ flag 18:31-18:36, 834431503-834431834 (There is a SEISMIC_X_30_100_MHZ flag for 19:03-19:08, and 19:11-19:12, but there is no obvious effect in range, and seem to be after the small EQ?).
61		859714881-859719931	14.6+/-1.9	Apr 04 2007 09:41:07 UTC	Several EQs affect the end of this segment, and the end of the previous segments. For this, one (the one most seriously affected), EQ flag 10:34-11:05, or 859718054-859719931
62		847876921-847880665	12.4+/-1.8	Nov 18 2006 09:21:47 UTC	EQ (t=-4), trouble in SenseMon starts at 10:09. High threshold seismic flag starts at 10:12:46, low threshold at 10:11:46.  DQ flag for end of this segment, 847879754-847880665.
63		874369184-874373675	14.8+/-1.8	Sep 21 2007 00:19:30 UTC	See Rank #3.
64		865778044-865780264	14.0+/-1.8	Jun 13 2007 13:53:50 UTC	PD_overflow flag at 865778572.
65		828175034-828182026	10.2+/-1.8	Apr 04 2006 08:37:00 UTC	Dan: "Post-commissioning glitches, noted in ops log. Saturations in AS1.". I suggest a "glitchy for unknown reason" for this segment.
66		846621055-846623580	11.6+/-1.8	Nov 03 2006 20:30:41 UTC	Std caused by last point alone. No flag needed.
67		826000844-826003433	8.2+/-1.8	Mar 10 2006 04:40:30 UTC	Dan: "Wind and microseism, same as L1-53 and 54". (L1-54 is the glitchy segment starting at 7:01, Rank #101). The glitchiness stopped when the useism noise went down. This FOM1 shows the segments following the ones in the plot. I suggest a "glitchy due to useism" for segments from L1-1185 (this one) up to L1-1197 (included), or GPS 826000845-826041719 .
68		826188494-826194040	10.7+/-1.8	Mar 12 2006 08:48:00 UTC	Problem traced to an RBS M1 railing, due to a  misaligned beam, fixed on Mar 14. Data from minute trends of L1:IOO-RBS_M1YAW_OUT16 with gps 826* show that there are several different science segments that end with railing of this channel: end of L1-1201, 826080840-826081316 end of L1-1204, 826106100-826106772 end of L1-1205, 826117500-826118315 end of L1-1216, 826180980-826181710 end of L1-1218, 826193760-826194040 end of L1-1225, 826260300-826261193 No times with gps 825* have control signals reaching saturation of +/- 10 Volts. The problem at the beginning of this segment is not due to RBS railing, but the operator mentions  the dropping range was improved with recentering of WFS2. I suggest also flagging  8:40-9:04 UTC (826188060-826189140) with "WFS2 trouble".
69		841189756-841197706	12.5+/-1.8	Sep 01 2006 23:49:02 UTC	See Rank #12, Ernesto flag.
70		821799414-821805955	8.6+/-1.8	Jan 20 2006 13:36:40 UTC	Dan's note, for this and the segment ranked next: "Busted LVEA seismometer. " Seismometer saga, reconstructed, with attached plot, with T=0 on Jan 18, 16:00 UTC.  On Tuesday 1/17,  the LVEA STS2 seismometer was mistakenly moved to a different location (this seismometer is used for sensor correction in BSC1, but it was moved near HAM1). This is seen in the plot happening at t~-22 hrs. The useism noise was high at the time, so there was no data for more than a day surrounding the move. On Fri 1/20, excess seismic noise in the LVEA seismometer is noticed by Tom Evans; looking back, the first seismic FOM1 showing trouble in LVEA_STS2_Y is Wed 1/18 ~16 UTC, at t=0 in the plot, although the excess comes and goes throughout the week (and it doesn't start immediately after the seismometer move). Finally the seismometer move was noticed, and while moving it back to the right place, the seismometer was damaged. Science mode is stopped until the seismometer is replaced a day later. The seismometer breaks at T~+50 hrs in the plot. The 0.03-0.1Hz blrms trend indicates times when the LVEA seismometer has a significantly larger signal than the EMTY seismometer; this is probably an indication of malfunction due to the move, or maybe wind. In either case it does affect the range, but not in a deterministic manner: it is probably the combination of noise in different bands. Segments "definitely"(?) affected: L1-588-593, 821712269-821732775 on Jan 19. (Notice: it doesn't include this or next ranked segment plots!). Segments with a moved seismometer, but not direct evidence of it causing problems: L1-576-611, or GPS 821663151-821805955. The segment here and next ranked one, during the owl shift, seem to be affected by large and increasing microseismic noise, producing lots of overflows and AS triggers. Not clear why the clean segment at t~[-3,-1] in this plot is clean, it has very large useism noise and daytime noise starting to grow. Suggest a large useism flag for segments L1-599-611, or 821768263-821805955.
71		821776524-821780346	9.4+/-1.8	Jan 20 2006 07:15:10 UTC	See useism flag above.
72		817161029-817167187	8.2+/-1.8	Nov 27 2005 21:10:16 UTC	(This segment contains the loudest candidate in the low mass S5 1st year search. ) SciMon A. Rodriguez recommends flagging this segment (#128) so that it is not used for data analysis. He also recommends flagging the last 10' of the next segment (#129), due to an arriving earthquake. Segment #122 is also ended for debugging the ugly glitching, #123 is also bad but short. L1-122: 817118583- 817119830 L1-128: 817161029- 817167187 L1-129 (end): 817171100-817171758
73		822248559-822250953	9.7+/-1.8	Jan 25 2006 18:22:25 UTC	Dan's note: "Wind, construction noise, and a large x-end seismic spike." Winds seems to be the trigger for the glitchiness in the second half of this segment. Wind DQ flag for 822249840-822250953.
74		872084427-872086651	14.9+/-1.8	Aug 25 2007 13:40:13 UTC	Train DQ flag at the end of the segment: 872085930 872087070.
75		836728706-836737320	13.7+/-1.8	Jul 12 2006 08:38:12 UTC	Large drop is due to an injection: L1:INJECTION:V99  836733921 836733985 plus overflows at the end. Nothing else needed.
76		839882175-839884542	13.0+/-1.8	Aug 17 2006 20:36:01 UTC	Dan's notes: "Short segment dominated by IFO warm-up, plus a deep glitch". The last few seconds have an overflow already flagged.
77		840630692-840635294	13.7+/-1.7	Aug 26 2006 12:31:18 UTC	See notes on Rank#8.
78		873575751-873581330	11.9+/-1.7	Sep 11 2007 19:55:37 UTC	Small earthquake. EQ flag for whole segment, 873575751-873581330
79		824391646-824395711	10.2+/-1.7	Feb 19 2006 13:40:32 UTC	Dan's notes:"An ETM drumhead mode changed frequency due to a temperature change in the endstation.  The big, undamped internal mode oscillations (around 7kHZ) saturated the front end processors and created gain peaking in the DARM loop." DQ flag already covering this: L1:BAD_SENSING:V99:  824394400  824395712
80		827150850-827154289	11.6+/-1.7	Mar 23 2006 12:07:16 UTC	Dan's notes: "Train (and an unexplained deep glitch)". Train at the end (DQ flag TRAIN_LIKELY:V99 827153670 827154290). Glitch is unflagged, but it's not enough for a "glitchy" flag.
81		841010916-841014473	13.8+/-1.7	Aug 30 2006 22:08:22 UTC	Dan's notes:"No explanation.  Probably related to saturations due to high-power operations". DQ gets better when power is lowered (longer, less sensitive segment). Suggest DQ flag for these segments with high power, L1-2953-2957, GPS 841009334-841018128.
82		857064505-857066921	13.8+/-1.7	Mar 04 2007 17:28:11 UTC	The end is an overflow, the glitchy beginning probably due to wind is not worth a flag.
83		826027451-826031914	9.0+/-1.7	Mar 10 2006 12:03:57 UTC	See Rank#67.
84		837454852-837458600	12.2+/-1.7	Jul 20 2006 18:20:38 UTC	Se Rank#7.
85		864140365-864143846	13.1+/-1.7	May 25 2007 14:59:11 UTC	EX-logging, see rank#9.
86		817214813-817218063	8.0+/-1.7	Nov 28 2005 12:06:40 UTC	See Rank#52.
87		848954405-848957340	11.2+/-1.7	Nov 30 2006 20:39:51 UTC	A single bad point at the beginning, maybe due to power raise. No explanation but not worth a glitchy flag.
88		854981293-854984066	13.3+/-1.7	Feb 08 2007 14:47:59 UTC	No obvious cause, but it isn't sustained glitching.
89		842773914-842781337	13.4+/-1.7	Sep 20 2006 07:51:40 UTC	L1:TRAIN_LIKELY:V99: 842780550 842781337.
90		864671842-864676426	13.9+/-1.7	May 31 2007 18:37:08 UTC	Standard deviation due to slow warmup.
91		822237058-822239811	9.9+/-1.7	Jan 25 2006 15:10:44 UTC	Dan's notes:"No clear explanation, but SEC construction was frequently mentioned in ops logs". Wind/construction DQ flag: 822237058-822239811
92		869726355-869733527	13.2+/-1.7	Jul 29 2007 06:39:01 UTC	Starts with a slow warmup, ends with a train, but no train flag? Jake has this interval 869733090 869734050 in his list, but flags downloaded on Jan 22 are only up to Nov 2006 (S5 first year). Check flags with Laura/Jake/Keith.
93		833672842-833675163	12.8+/-1.7	Jun 06 2006 23:47:08 UTC	Dan's notes: "HEPI configuration was off-nominal (a FIR filter wasn't turned on)". Standard deviation is due to single first bad point.
94		820265966-820268997	8.6+/-1.7	Jan 02 2006 19:39:12 UTC	Dan's notes:"Wind and anthropogenic seismic noise, leading to saturations of the PDs." Wind DQ flag 820265966-820268997
95		873308858-873311216	13.1+/-1.7	Sep 08 2007 17:47:24 UTC	Anthro noise produces glitchiness even with low power. High Seismic Noise DQ flag for L1-6208,6209: 873304452-873311216
96		859566249-859575270	12.6+/-1.7	Apr 02 2007 16:23:55 UTC	Large ueism plus daytime seismic noise (here and here) affects several science segments (here and here). This segment is L1-4870, previous one is Rank#111. The ones that follow have fewer glitches, but still have significantly larger scatter. Large useism DQ flag for L1-4869-4872, 859563210-859594699
97		818654827-818659505	8.3+/-1.7	Dec 15 2005 04:06:54 UTC	Dan's notes: "High microseism". Stormy weather makes for glitchy segments, although most are very short (this is the only one longer than 2048sec). Storm DQ flag for L1-261-276, 818638317-818666614
98		825217654-825238539	9.2+/-1.7	Mar 01 2006 03:07:20 UTC	See Rank#42.
99		821388900-821393614	9.3+/-1.7	Jan 15 2006 19:34:46 UTC	Dan's note:"Some logging & wind; no good explanation". Glitchy for unknown reason, since 19:00 UTC: 821386814-821393614
100		865860613-865864192	12.7+/-1.7	Jun 14 2007 12:49:59 UTC	Two trains, at the beginning and end of this segment, flagged at 865860690-865861650 and 865863270-865864230. There is an earthquake at the beginning of the next segment (13:50-15:00 UTC), and another one in the next segment (18:00-20:00). EQ flags: 865864214-865868414; 865879214-865886414
101		826009322-826011978	8.6+/-1.7	Mar 10 2006 07:01:48 UTC	See Rank #67.
102		822324033-822326345	9.7+/-1.7	Jan 26 2006 15:20:19 UTC	Dan's notes:"Just before a train, but no clear reason for deep glitches". Train is flagged 12min after the end of this segment (not in science mode). Ops at 15:58 (end of segment):"Lost lock, construction forklift". Forklift not obvious in seismic trends, but we'll take the operator's word to flag the glitchy minutes: Forklift DQ flag: 822325680-822326345
103		872570016-872575242	14.0+/-1.6	Aug 31 2007 04:33:22 UTC	See Rank#35.
104		841179858-841183428	11.4+/-1.6	Sep 01 2006 21:04:04 UTC	See Rank #12, Ernesto flag.
105		871917137-871919472	14.1+/-1.6	Aug 23 2007 15:12:03 UTC	Overflow flags exist for large dip at the end, plus L1:MASTER_OVERFLOW_ASC:V99 871919131 871919135
106		816443252-816446042	8.7+/-1.6	Nov 19 2005 13:47:19 UTC	Op says EQ in Indonesia breaks the lock; SenseMon begins having trouble at 14:29 UTC, 6.5 EQ starts at 14:10 (Lat=2deg, Long=97deg). EQ flag 14:28-14:33, 816445693-816446042
107		817048430-817050840	8.0+/-1.6	Nov 26 2005 13:53:37 UTC	Dan's note:"Unexplained glitching; possibly related to bad HEPI PenTek". Glitchiness for unknown reason flag, 817048430-817050840
108		816737834-816749451	8.8+/-1.6	Nov 22 2005 23:37:01 UTC	See Rank#16.
109		865780920-865786190	13.5+/-1.6	Jun 13 2007 14:41:46 UTC	A couple of glitches probably due to EX 3-10 Hz seismic noise, but not enough evidence for a glitchy flag.
110		818987271-818992566	9.9+/-1.6	Dec 19 2005 00:27:38 UTC	SenseMon begins dropping at 01:41; 4.9 EQ starts at 01:38 (Lat=4.20,Long=-84.08, Pacific Ocean, ~600km from Panama/Colombia coasts). EQ flag 1:38-1:56, 818991493-818992566
111		859563210-859566167	10.9+/-1.6	Apr 02 2007 15:33:16 UTC	See Rank#96.
112		861015368-861018489	13.1+/-1.6	Apr 19 2007 10:55:54 UTC	Op Note (Dan Hoak): "Data from L1 after 11:19, and until the end of the segment at 11:48, should be flagged as unreliable." GPS 861016754-861018489
113		859131251-859133979	13.2+/-1.6	Mar 28 2007 15:33:57 UTC	Std due to slow warm up.
114		823076171-823080540	9.1+/-1.6	Feb 04 2006 08:15:57 UTC	EQ ends the segment, but it doesn't affect the time in science mode. Large microseismic noise affects the the segments before this one. Large useism flag:  L1-811-814, GPS 823059304-823080540
115		843665786-843675218	13.7+/-1.6	Sep 30 2006 15:36:12 UTC	Mag 6.00 EQ in Peru, starts at source at 16:27, arrives at LLO at ~16:42, lasts ~30min in the middle of this segment. Mag 6.60  EQ  near Japan starts at source at 17:50, arrives at ~18:00 (segment ends at 18:13). EQ flags: 16:40 - 17:15 = 843669614-843671714 17:59 - 18:13 = 843674354-843675218
116		862694322-862699740	14.1+/-1.6	May 08 2007 21:18:28 UTC	Large std deviation due to single glitch, L1:PHOTODIODE_GLITCH:V99 862697820 862697880
117		841382073-841386990	13.6+/-1.6	Sep 04 2006 05:14:19 UTC	L1:TRAIN_LIKELY:V99.txt:3007 841386330 841386991 Beginning is a bit noisy due to wind, but probably not worth a flag. Previous segment, L1-3006, has a problem at the end with railing RBS, 841379700-841380586. No other times with gps 841* showed PZT saturation.
118		862845555-862851227	14.2+/-1.6	May 10 2007 15:19:01 UTC	L1:BS_OPTLEVER:V99 862846748 862846753 These segments have problems with BS oplev, but the large drops in this segment does not correspond to the flagged seconds (the flag seems to coincide with smaller range drops). Maybe the BS is causing trouble not just visible in the BS SUM? Not enough evidence or glitchiness for a flag, but maybe we should investigate more...
119		826430694-826436982	11.0+/-1.6	Mar 15 2006 04:04:40 UTC	Dan's note:"Steadily Sinking Sensemon (bias module - same as #15)" DQ flag 826436220-826436982
120		840522535-840528273	14.1+/-1.6	Aug 25 2006 06:28:41 UTC	Train at the end: L1:TRAIN_LIKELY:V99 840527430 840528274
121		874158684-874163287	12.6+/-1.6	Sep 18 2007 13:51:10 UTC	(Segment has lower power, to sustain lock in daytime seismic noise) Not clear reason for lock loss, but a flag exists for the end minutes: L1:PHOTODIODE_GLITCH:V99 874163100 874163280
122		837458706-837461030	12.3+/-1.6	Jul 20 2006 19:24:52 UTC	See Rank#7.
123		868554359-868560258	12.9+/-1.6	Jul 15 2007 17:05:45 UTC	Slow warm up, plus a glitch (no flags, but we shouldn't add one).
124		818422069-818427181	9.5+/-1.5	Dec 12 2005 11:27:36 UTC	Dan's notes: "No explanation.  Beginning-of-run glitching." Previous segment is Rank #134 DQ flag for end of this segment: 818426329-818427181, and end of previous one, 818416609-818419984.
125		818578313-818586542	9.9+/-1.5	Dec 14 2005 06:51:40 UTC	Large std due to several bad minutes at the end. Train DQ flag starts after the segment ends: 818586810-818587770 L1:SEVERE_LSC_OVERFLOW:V99  818586336 818586338 (and others follow). Nothing else needed.
126		834079237-834094194	14.2+/-1.5	Jun 11 2006 16:40:23 UTC	Segment ends with EQ, next segment is noisy due to Tropical storm Alberto, although the beginning is still affected by the earthquake. L1:SEISMIC_X_30_100_MHZ_HIGHTHRESH:V99 834093780 834094140 L1:SEISMIC_Y_30_100_MHZ_HIGHTHRESH:V99 834094080 834094140 First minute with SenseMon affected is 834092750, earlier than seismic flags (lower thresholds are not very different). EQ DQ flag: 834092750-834099294
127		835216184-835222858	12.9+/-1.5	Jun 24 2006 20:29:30 UTC	L1:SEISMIC_Y_30_100_MHZ_HIGHTHRESH:V99 835222800 835222859 L1:SEISMIC_Y_30_100_MHZ_LOWTHRESH:V99 835222620 835222859 Effect in SenseMon appears earlier than the seismic flags. EQ flag: 835220090-835222858
128		841099917-841105772	12.1+/-1.5	Aug 31 2006 22:51:43 UTC	See Rank#26.
129		855835832-855852129	12.1+/-1.5	Feb 18 2007 12:10:18 UTC	Many ASI-CORR overflows flagging glitches in this segment, microseismic noise was very high.
130		848071105-848073335	10.7+/-1.5	Nov 20 2006 15:18:11 UTC	Overflow flags for the last minute; there is also a seismic flag: L1:SEISMIC_X_30_100_MHZ_HIGHTHRESH:V99 848072880 848072940 indicating a small (?) earthquake near the middle of the segment.
131		862827654-862831693	14.3+/-1.5	May 10 2007 10:20:40 UTC	There are overflow flags for the end of the segment.
132		836066137-836074080	13.7+/-1.5	Jul 04 2006 16:35:23 UTC	L1:TRAIN_LIKELY:V99 836073390 836074081
133		840024977-840029642	13.8+/-1.5	Aug 19 2006 12:16:03 UTC	L1:TRAIN_LIKELY:V99 840028890 840029642
134		818410637-818419984	9.6+/-1.5	Dec 12 2005 08:17:04 UTC	See Rank#124.
135		832704395-832724118	13.5+/-1.5	May 26 2006 18:46:21 UTC	L1:SEISMIC_Y_30_100_MHZ_HIGHTHRESH:V99 832723740 832724100 L1:SEISMIC_X_30_100_MHZ_LOWTHRESH:V99 832721280 832724119 SenseMon is affected by EQ at even earlier times than low threshold flag: EQ flag: 832720390-832724118
136		840841518-840851520	14.5+/-1.5	Aug 28 2006 23:05:04 UTC	Large std due to last point; no obvious reason to flag the whole segment.
137		865724248-865736488	13.8+/-1.5	Jun 12 2007 22:57:14 UTC	Large std due to slow warm up.
138		866839242-866844245	13.0+/-1.5	Jun 25 2007 20:40:28 UTC	Slow warm up, anthro noise is decreasing during the segment too. No flag needed.
139		869489953-869492206	12.7+/-1.5	Jul 26 2007 12:58:59 UTC	Last minute has an overflow; daytime seismic noise produces the other glitches, no flag needed.
140		857924245-857931277	14.1+/-1.5	Mar 14 2007 16:17:11 UTC	No obvious reasons for glitches, maybe wind? although neither op nor scimon mention this is a glitchy segment. No flag needed, IMHO.
141		839231699-839245031	13.9+/-1.5	Aug 10 2006 07:54:45 UTC	Several seismic flags, but they start after the EQ begins affecting SenseMon: L1:SEISMIC_X_30_100_MHZ_MEDTHRESH:V99 839232840 839233920 (earliest) L1:SEISMIC_X_30_100_MHZ_HIGHTHRESH:V99 839233800 839233920 (~15' after the lowest range) From SenseMon, EQ flag should be for the first 50' of the segment: 839231699-839234699
142		861112311-861116712	14.5+/-1.5	Apr 20 2007 13:51:37 UTC	Last minute has overflows. Train in Jake's list: 861116550-861117510. No other flag needed.

Proposed Data Quality Flags