16 October 2001 --

Week 297 results (2001 October 5 - 11)

• GX 354-0 (X1728-34) - < 30 mCrab, the lowest intensity in the ASM record for this source
• X1745-203 (in NGC 6440) - decreased a small amount to ~130 mCrab
• KS 1947+300 - ~15 mCrab
• Cyg X-1 - strong and flaring up to 1.7 Crab

9 October 2001 --

Week 296 results (2001 September 28 - October 4)

• X1246-588 - stronger than usual at ~20 mCrab
• XTE J1650-500 - ~380 mCrab
• X1745-203 (in NGC 6440) - ~170 mCrab
• KS 1947+300 - ~13 mCrab
• Cyg X-1 - active mostly in the 0.5 to 1.0 Crab range
• Cyg X-3 - at ~100 mCrab in daily averages is much quieter than it has been for 3 months

Note: Last week's reports of increases in the fluxes of SGR 1806-20, GS 1826-238, and possibly also SAX J1747-2843 are likely to be incorrect. These may be attributed to the outburst of X1745-203 and to an urgent need for the ASM position calibration files to be updated. The ASM light curves have been corrected for the increase in intensity of X1745-203 and work is in progress on updating the calibration.

1 October 2001 --

Week 295 results (2001 September 21 - 27)

• XTE J1650-500 - after a small decline in strength is ~400 mCrab
• X 1745-203 - increased sharply to ~170 mCrab, by far the strongest flux for this source in the ASM light curve
• SAX J1747.0-2853 - could be ~50 mCrab
• SAX J1750.8-2900 - ~30 mCrab
• SGR 1806-20 - could be up to ~25 mCrab
• GS 1826-238 - persistent flux is up sharply to ~130 mCrab

24 September 2001 --

Week 294 results (2001 September 14 - 20)

• EXO 0748-676 - a bit stronger than usual at ~15 mCrab
• XTE J1650-500 - rose to ~520 mCrab, but a peak at the week 295 quick look results for this source indicate that this rising trend does not continue
• X 1730-333 (Rapid Burster) - declined to < 10 mCrab
• X 1745-203 - ~40 mCrab, very high for this source
• SAX J1750.8-2900 - ~40 mCrab
• AX J1820.5-1434 - strong and active, with daily average fluxes as high as 100 mCrab
• RX J1826.2-1450 - may be up to ~40 mCrab (very high for this source in the ASM record)
• GRS 1915+105 - strong and active w/ 90 s average flux as high as 3.0 Crab
• Cyg X-1 - varied around 1 Crab

17 September 2001 --

Week 293 results (2001 September 7 - 13)

• XTE J1650-500 - roughly steady for 5 days at ~350 mCrab
• X 1730-333 (Rapid Burster) - still active but decaying w/ strength ~40 mCrab
• AX J1820.5-1434 - appears to be varying up to ~80 mCrab, but this could be systematic noise of undetermined cause (the Sun is not near this part of the sky)
• Cyg X-1 - flared to 1.5 Crab

10 September 2001 --

Week 292 results (2001 August 31 - September 6)

• EXO 0748-676 - still relatively strong at ~13 mCrab
• Cen X-3 - below 50 mCrab
• XTE J1650-500 - this is a new previously undiscovered (to our knowledge) transient source (see report by Remillard in IAU Circular) that reached ~300 mCrab by the end of the week
• X1730-333 (Rapid Burster) - looks newly active with strengths to ~200 mCrab

4 September 2001 --

Week 291 results (2001 August 24 - 30)

• EXO 0748-676 - may be somewhat stronger than usual at ~13 mCrab
• X1746-370 - weaker than usual at <10 mCrab
• KS 1947+300 - still looks like ~15 mCrab

27 August 2001 --

Week 290 results (2001 August 17 - 23)

• X0614+091 - is only about 25 mCrab; this is rather a rather weak level for this source compared to the earlier ASM history
• Cen X-3 - declining; now about 40 mCrab or less
• XTE J1543-568 - may be up to ~30 mCrab
• KS 1947+300 - may be up to ~15 mCrab

22 August 2001 --

Week 289 results (2001 August 10 - 16)

• Cen X-3 - appears to be decreasing in strength from the recent high state; ~80 mCrab out of eclipse
• X1658-298 - ~10 mCrab as opposed to the ~40 mCrab flux of the last 500 or so days
• AX J1820.5-1434 - the flux averaged ~70 mCrab on the last two days of the week; quicklook data from week 290 show a strength of ~20 mCrab which is still higher than the ASM long-term average flux

13 August 2001 --

Week 288 results (2001 August 3 - 9)

• Cen A - ~15 mCrab (on the high side but not at a unprecedented level for this source)
• X1708-407 - ~40 mCrab (not unusual)
• BL Lac object 1722+119 - ~6 mCrab (i.e., weak to modest evidence for emission at a few to about 6 mCrab)
• X1745-203 (in glob cl. NGC 6440) - ~50 mCrab; very high for this source in the ASM record

7 August 2001 --

Week 287 results (2001 July 27 - August 2)

• X1708-407 - observations from the last few days of the week suggest that this object could be as strong as 70 mCrab
• Aql X-1 - could be about 10 mCrab
• X1916-053 - up to ~20 mCrab
• PKS 2155-304 - ~20 mCrab, an exceptional strength for this source

30 July 2001 --

Week 286 results (2001 July 20 - 26)

• X1657-415 - There are (not completely clear) signs that this is active w/ flux occasionally approaching 40 mCrab
• NGC 6441 (source in glob. cl.) - ~25 mCrab
• Aql X-1 - <13 mCrab
• PKS 2155-304 - may be about 13 mCrab
• 4U 2206+54 - up to ~13 mCrab

25 July 2001 --

Week 285 results (2001 July 13 - 19)

• LMC X-3 - up to ~13 mCrab
• X1708-407 - somewhat stronger than usual at about 50 mCrab
• GX 17+2 - the analysis problem noted last week has been corrected and all the low points have disappeared
• Aql X-1 - strength gradually diminished to ~13 mCrab
• GRS 1915+105 - strong and highly variable; up to 1.7 Crab
• 4U 2206+54 - possibly up to 10 mCrab

16 July 2001 --

Week 284 results (2001 July 6 - 12)

• GRS 1758-258 - ~80 mCrab, the strongest reliable detection of this source by the ASM
• GX 17+2 - a number of low points in the light curve are believed to be due to a software problem (which is currently being corrected) and should be disregarded until further notice
• Aql X-1 - slowly rose to ~50 mCrab
• GRS 1915+105 - has been low (~430 mCrab) and steady for about 2 weeks
• Cyg X-1 - flared to 1.3 Crab (as seen in 90 s averages)

9 July 2001 --

Week 283 results (2001 June 29 - July 5)

• GX 354-0 (X1728-34) - over 100 mCrab (on the strong side for the last year or so)
• XTE J1837+037 - <13 mCrab
• Aql X-1 - decreased to ~20 mCrab; a full outburst does not appear to be developing

2 July 2001 --

Week 282 results (2001 June 22 - 28)

• Cen X-3 - up to ~260 mCrab
• Cen A - ~20 mCrab (relatively high for this object)
• X1636-536 - decreased to ~65 mCrab, the lowest X-ray flux in 5 years
• X1730-333 (Rapid Burster) - < 13 mCrab
• XTE J1837+037 - ~13 mCrab
• Aql X-1 - rose to ~50 mCrab

27 June 2001 --

Week 281 results (2001 June 15 - 21)

• X1730-333 (Rapid Burster) - declined irregularly, and was below 13 mCrab at the end of the week
• SAX J1818.6-1703 - possibly up to ~30 mCrab
• XTE J1837+037 - possibly up to ~25 mCrab

21 June 2001 --

Week 280 results (2001 June 8 - 14)

• X1730-333 (Rapid Burster) - still somewhat active (up to ~50 mCrab)
• X1916-053 - ~25 mCrab (not very unusual)
• 3A 1942+274 - up to ~15 mCrab

12 June 2001 --

Week 279 results (2001 June 1 - 7)

• GX 301-2 - is still varying in the range 0 - 50 mCrab in a manner that does not appear to be synchronized to its orbital period; this is somewhat unusual
• X1323-619 - up to ~25 mCrab, the highest or nearly highest flux during the RXTE mission
• 4U 1630-472 - <10 mCrab
• X1657-415 - active again, i.e., up to ~40 mCrab
• 4U 1705-440 - up to nearly 400 mCrab

5 June 2001 --

Week 278 results (2001 May 25 - 31)

• 4U 1630-472 - down to ~< 13 mCrab
• 4U 1705-440 - above 0.3 Crab
• X1730-333 (Rapid Burster) - down to ~80 mCrab
• SAX J21035+4545 - back up to ~13 mCrab

29 May 2001 --

Week 277 results (2001 May 18 - 24)

• X0918-548 - up to ~20 mCrab (possibly the highest intensity of this source in the ASM era)
• 4U 1630-472 - down to ~25 mCrab
• X1730-333 (Rapid Burster) - rose to ~130 mCrab early in the week
• SAX J1750.8-2900 - ~40 mCrab
• SAX J21035+4545 - below 10 mCrab

21 May 2001 --

Week 276 results (2001 May 11 - 17)

• 4U 1630-472 - down to ~60 mCrab
• X1636-536 - down to ~70 mCrab, the weakest level that this source has exhibited in 5 years of ASM data
• GX3+1 - this week's results are noisy and lower than expected (~140 mCrab); it is not entirely clear that the low intensity is a reliable result
• NGC 6712 (X1850-087) - up to ~20 mCrab, which is a record high in the ASM data
• KS 1947+300 - below 10 mCrab

17 May 2001 --

Week 275 results (2001 May 4 - 10)

• BL 0323+022 - could be up to 50 mCrab (but this comes at a time that suggests it is the result of contamination by solar X-rays)
• Cen X-3 - pretty strong with flares to 500 mCrab
• 4U 1630-472 - decreased to ~100 mCrab
• 3A 1942+274 - < 10 mCrab
• KS 1947+300 - < 10 mCrab

9 May 2001 --

Week 274 results (2001 April 27 - May 3)

• GX 301-2 - has been persistently active (20 - 60 mCrab) for more than 2 weeks
• X1246-588 - around 13 mCrab
• X1538-522 - ~15 mCrab
• 4U 1630-472 - still ~130 mCrab
• SAX J1750.8-2900 - still nearly 50 mCrab
• KS 1947+300 - down to ~10 mCrab

30 April 2001 --

Week 273 results (2001 April 20 - 26)

• X0114+650 - possibly up to ~13 mCrab
• LMC X-3 - is declining in strength, now < 13 mCrab
• 4U 1705-440 - increased to ~130 mCrab
• SAX J1750.8-2900 - at about 65 mCrab
• KS 1947+300 - down to ~15 mCrab

23 April 2001 --

Week 272 results (2001 April 13 - 19)

• Mkn 421 - down to a modest 10 mCrab or so
• Cen X-3 - is showing signs of reawakening after 3 months of quiescence, i.e, up to 60 mCrab
• XTE J1550-564 - is very weak, < 10 mCrab
• 4U 1630-472 - still near 130 mCrab
• SAX J1750.8-2900 - up to 100 mCrab and still rising
• 3A 1942+274 - up to ~15 mCrab
• KS 1947+300 - ~25 mCrab

18 April 2001 --

Week 271 results (2001 April 6 - 12)

• 4U 1630-472 - continues to stay at ~140 mCrab
• SAX J1750.8-2900 - rose a little to ~60 mCrab
• SAX J21035+4545 - down to < 15 mCrab

Note: The Sun has been very active with strong flares and CMEs that often disrupt ASM observations.

9 April 2001 --

Week 270 results (2001 March 30 - April 5)

• 4U 1630-472 - ~160 mCrab
• KS1731-260 - below 15 mCrab
• E17407-2942 - ~50 mCrab
• SAX J1750.8-2900 - ~50 mCrab
• KS1947+300 - down to ~30 mCrab
• Cyg X-3 - activity has gone down some, so that the daily average intensity is now ~160 mCrab
• SAX J21035+4545 - up to ~25 mCrab, the highest intensity in the ASM record for this source

2 April 2001 --

Week 269 results (2001 March 23 - 29)

• Mkn 421 - consistently >~ 40 mCrab
• X1323-619 - ~25 mCrab
• XTE J1550-564 - appears to be weak or not detected (<15 mCrab)
• 4U 1630-472 - increased in flux; was in the range 130 - 200 mCrab
• KS 1947+300 - ~40 mCrab
• SAX J21035+4545 - appears to be rising to ~25 mCrab

28 March 2001 --

Week 268 results (2001 March 16 - 22)

• Mkn 421 - flared to ~45 mCrab for ~1 day
• XTE J1550-564 - possibly rose to ~50 mCrab but the data quality is not excellent

19 March 2001 --

Week 267 results (2001 March 9 - 15)

• Mkn 421 - somewhat weaker than last week; in the range 20 to 40 mCrab
• 4U 1630-472 - up to about 80 mCrab
• X1702-429 - roughly 40 mCrab based on relatively noisy data
• SAX J1750.8-2900 - ~40 mCrab
• KS 1947+300 - down to ~55 mCrab

12 March 2001 --

Week 266 results (2001 March 2 - 8)

• Mkn 421 - still strong and variable with daily average intensity as high as 60 mCrab
• XTE J1550-564 - decreased to < 15 mCrab
• 4U1630-472 - appears to be climbing slowly and has reached ~30 mCrab
• X1702-429 - up to ~65 mCrab
• XTE J1723-376 - again at ~20 mCrab
• X1730-333 (Rapid Burster) - at or below ~15 mCrab
• SAX J1747.0-2853 - roughly 20 mCrab
• SAX J1750.8-2900 - rose to ~120 mCrab and then declined to ~35 mCrab
• GRS 1915+105 - mostly low and steady with intensities in the range 0.3 to 0.6 Crab

Note: The analysis of the week 265 ASM data improperly attributed flux from SAX J1750 to SAX J1747 which did not exceed 25 mCrab in the ASM daily average intensities. This has been corrected for week 266.

5 March 2001 --

Week 265 results (2001 February 23 - March 1)

• Mkn 421 - went up to ~70 mCrab and then down to ~30 mCrab
• XTE J1723-376 - up to nearly 25 mCrab
• X1730-333 (Rapid Burster) - still chugging along at ~50 mCrab
• SAX J1747.0-2853 - rose to ~40 mCrab at week's end
• KS 1947+300 - ~80 mCrab

26 February 2001 --

Weeks 264 results (2001 February 16 - 22)

• Mkn 421 - appears to have weakened to ~15 mCrab
• XTE J1550-564 - ~30 mCrab
• X1636-536 - a flare-like event occurred late in the week with flux as high as 0.8 Crab
• X1730-333 (Rapid Burster) - down to ~40 mCrab
• Cyg X-1 - weakened considerably, down to ~0.25 Crab

20 February 2001 --

Weeks 263 results (2001 February 9 - 15)

• Mkn 421 - this BL Lac still active, near 25 mCrab
• 1ES 1212+078 - another BL Lac, possible outburst to 9 mCrab
• XTE J1550-564 - BHC still in weak outburst; variable, near 40 mCrab
• X1730-333 - Rapid burster 100 mCrab at end of week
• GRS 1915+105 - outbursts above 1 Crab
• KS 1947+300 - pulsar, continues slow rise, 120 mCrab
• Cygx1 - back down to 400 mCrab
• Cygx3 - fast rise to 400 mCrab

12 February 2001 --

Weeks 262 results (2001 February 2 - 8)

• Mkn 421 - down to ~30 mCrab
• XTE J1550-564 - up to ~100 mCrab (on the basis of only a few observations)
• HD154791 (CV) - up to ~15 mCrab
• KS 1947+300 - up to ~120 mCrab

5 February 2001 --

Weeks 261 results (2001 January 26 - February 1)

• Cen X-3 - is now in a low state below 20 mCrab
• XTE J1550-564 - is up to ~40 mCrab
• KS 1947+300 - ~90 mCrab
• Cyg X-1 - active in the range 0.5 to 1.6 Crab

29 January 2001 --

Weeks 260 results (2001 January 19 - 25)

• Mkn 421 - daily average strong and highly variable (25 - 70 mCrab)
• 4U 1630-472 - decreased to ~25 mCrab
• Her X-1 - another main "on" state appeared on schedule
• KS 1947+300 - up to ~100 mCrab (record strength for the ASM)
• Cyg X-1 - shows moderate flaring (0.6 to 1.3 Crab)

22 January 2001 --

Weeks 259 results (2001 January 12 - 18)

• Mkn 421 - very strong at ~45 mCrab (record strength for the ASM)
• 4U 1630-472 - down to ~50 mCrab
• KS 1947+300 - still above 50 mCrab (based on few observations)

16 January 2001 --

Weeks 257-258 results (2000 December 29 - 2001 January 11)

• Mkn 421 - ~25 mCrab
• HD101379 (RS CVn system) - ~20 mCrab
• X1608-522 - relatively weak again, ~20 mCrab or less (based on a small number of observations)
• 4U1630-47 - in the 70 to 130 mCrab range (also based on a small number of observations)

4 January 2001 --

Week 256 results (2000 December 22 - 28)

• Her X-1 has returned to a low state (< 10 mCrab) as expected
• KS 1947+300 - rose to nearly 50 mCrab

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