Gamma-ray Burst 090509

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sat 09 May 09 05:10:20 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      44
TRIGGER_NUM:     263538607
GRB_RA:          220.150d {+14h 40m 36s} (J2000),
                 220.295d {+14h 41m 11s} (current),
                 219.378d {+14h 37m 31s} (1950)
GRB_DEC:         -36.650d {-36d 38' 59"} (J2000),
                 -36.690d {-36d 41' 22"} (current),
                 -36.436d {-36d 26' 09"} (1950)
GRB_ERROR:       25.97 [deg radius, statistical plus systematic]
GRB_INTEN:       74 [cnts/sec]
DATA_SIGNIF:     4.90 [sigma]
INTEG_TIME:      2.048 [sec]
GRB_DATE:        14960 TJD;   129 DOY;   09/05/09
GRB_TIME:        18605.72 SOD {05:10:05.72} UT
GRB_PHI:         200.00 [deg]
GRB_THETA:        90.00 [deg]
DATA_TIME_SCALE: 2.0480 [sec]
HARD_RATIO:      0.51
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      95%  GRB
2nd_MOST_LIKELY:   4%  Generic Transient
DETECTORS:       0,0,0, 0,0,0, 0,0,1, 0,0,1, 0,0,
SUN_POSTN:        46.26d {+03h 05m 03s}  +17.39d {+17d 23' 30"}
SUN_DIST:        160.00 [deg]   Sun_angle= -11.6 [hr] (East of Sun)
MOON_POSTN:      225.28d {+15h 01m 06s}  -22.10d {-22d 06' 07"}
MOON_DIST:        15.21 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      326.18, 21.25 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      229.26,-19.99 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 10.15,23.47 [deg].

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sat 09 May 09 05:10:30 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      57
TRIGGER_NUM:     263538607
GRB_RA:          240.333d {+16h 01m 20s} (J2000),
                 240.483d {+16h 01m 56s} (current),
                 239.534d {+15h 58m 08s} (1950)
GRB_DEC:         -33.417d {-33d 24' 59"} (J2000),
                 -33.442d {-33d 26' 31"} (current),
                 -33.277d {-33d 16' 37"} (1950)
GRB_ERROR:       22.78 [deg radius, statistical plus systematic]
GRB_INTEN:       60 [cnts/sec]
DATA_SIGNIF:     6.70 [sigma]
INTEG_TIME:      4.096 [sec]
GRB_DATE:        14960 TJD;   129 DOY;   09/05/09
GRB_TIME:        18605.72 SOD {05:10:05.72} UT
GRB_PHI:         193.00 [deg]
GRB_THETA:        75.00 [deg]
DATA_TIME_SCALE: 4.0960 [sec]
HARD_RATIO:      0.99
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      96%  GRB
2nd_MOST_LIKELY:   1%  SGR_1806n20
DETECTORS:       0,0,0, 0,0,0, 0,0,1, 0,0,1, 0,0,
SUN_POSTN:        46.26d {+03h 05m 03s}  +17.39d {+17d 23' 30"}
SUN_DIST:        159.49 [deg]   Sun_angle= 11.1 [hr] (West of Sun)
MOON_POSTN:      225.28d {+15h 01m 07s}  -22.10d {-22d 06' 09"}
MOON_DIST:        17.56 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      342.39, 14.54 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      244.96,-12.52 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 10.15,23.47 [deg].

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sat 09 May 09 05:10:44 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      68
TRIGGER_NUM:     263538607
GRB_RA:          241.883d {+16h 07m 32s} (J2000),
                 242.028d {+16h 08m 07s} (current),
                 241.109d {+16h 04m 26s} (1950)
GRB_DEC:         -28.800d {-28d 48' 00"} (J2000),
                 -28.824d {-28d 49' 27"} (current),
                 -28.667d {-28d 40' 01"} (1950)
GRB_ERROR:       15.48 [deg radius, statistical plus systematic]
GRB_INTEN:       120 [cnts/sec]
DATA_SIGNIF:     7.30 [sigma]
INTEG_TIME:      2.048 [sec]
GRB_DATE:        14960 TJD;   129 DOY;   09/05/09
GRB_TIME:        18605.72 SOD {05:10:05.72} UT
GRB_PHI:         188.00 [deg]
GRB_THETA:        75.00 [deg]
DATA_TIME_SCALE: 2.0480 [sec]
HARD_RATIO:      0.47
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      94%  GRB
2nd_MOST_LIKELY:   4%  Generic Transient
DETECTORS:       0,0,0, 0,0,0, 0,0,1, 0,0,1, 0,0,
SUN_POSTN:        46.26d {+03h 05m 03s}  +17.39d {+17d 23' 30"}
SUN_DIST:        161.57 [deg]   Sun_angle= 10.9 [hr] (West of Sun)
MOON_POSTN:      225.28d {+15h 01m 07s}  -22.10d {-22d 06' 11"}
MOON_DIST:        16.53 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      346.70, 16.96 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      245.37, -7.73 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 10.15,23.47 [deg].

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sat 09 May 09 05:11:27 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      56
TRIGGER_NUM:     263538607
GRB_RA:          214.850d {+14h 19m 24s} (J2000),
                 214.983d {+14h 19m 56s} (current),
                 214.142d {+14h 16m 34s} (1950)
GRB_DEC:         -23.330d {-23d 19' 47"} (J2000),
                 -23.373d {-23d 22' 20"} (current),
                 -23.100d {-23d 06' 01"} (1950)
GRB_ERROR:       11.29 [deg radius, statistical only]
DATA_SIGNIF:     8.00 [sigma]
DATA_INTERVAL:   4.096 [sec]
GRB_DATE:        14960 TJD;   129 DOY;   09/05/09
GRB_TIME:        18605.72 SOD {05:10:05.72} UT
GRB_PHI:         189.00 [deg]
GRB_THETA:        99.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   413 (Gnd S/W Version number)
SUN_POSTN:        46.26d {+03h 05m 03s}  +17.39d {+17d 23' 31"}
SUN_DIST:        167.86 [deg]   Sun_angle= -11.2 [hr] (East of Sun)
MOON_POSTN:      225.29d {+15h 01m 09s}  -22.10d {-22d 06' 16"}
MOON_DIST:         9.58 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      327.83, 35.25 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      220.29, -8.90 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sat 09 May 09 05:11:35 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      70
TRIGGER_NUM:     263538607
GRB_RA:          234.220d {+15h 36m 53s} (J2000),
                 234.357d {+15h 37m 26s} (current),
                 233.487d {+15h 33m 57s} (1950)
GRB_DEC:         -22.440d {-22d 26' 23"} (J2000),
                 -22.470d {-22d 28' 12"} (current),
                 -22.276d {-22d 16' 32"} (1950)
GRB_ERROR:       10.47 [deg radius, statistical only]
DATA_SIGNIF:     8.60 [sigma]
DATA_INTERVAL:   2.048 [sec]
GRB_DATE:        14960 TJD;   129 DOY;   09/05/09
GRB_TIME:        18605.72 SOD {05:10:05.72} UT
GRB_PHI:         183.00 [deg]
GRB_THETA:        83.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   413 (Gnd S/W Version number)
SUN_POSTN:        46.26d {+03h 05m 03s}  +17.39d {+17d 23' 31"}
SUN_DIST:        170.85 [deg]   Sun_angle= 11.5 [hr] (West of Sun)
MOON_POSTN:      225.29d {+15h 01m 09s}  -22.11d {-22d 06' 17"}
MOON_DIST:         8.40 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      345.88, 26.32 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      237.24, -2.98 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sat 09 May 09 05:11:29 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      67
TRIGGER_NUM:     263538607
GRB_RA:          228.470d {+15h 13m 53s} (J2000),
                 228.611d {+15h 14m 27s} (current),
                 227.718d {+15h 10m 52s} (1950)
GRB_DEC:         -28.320d {-28d 19' 11"} (J2000),
                 -28.354d {-28d 21' 15"} (current),
                 -28.134d {-28d 08' 02"} (1950)
GRB_ERROR:       16.84 [deg radius, statistical only]
DATA_SIGNIF:     6.80 [sigma]
DATA_INTERVAL:   4.096 [sec]
GRB_DATE:        14960 TJD;   129 DOY;   09/05/09
GRB_TIME:        18605.72 SOD {05:10:05.72} UT
GRB_PHI:         190.00 [deg]
GRB_THETA:        86.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   413 (Gnd S/W Version number)
SUN_POSTN:        46.26d {+03h 05m 03s}  +17.39d {+17d 23' 31"}
SUN_DIST:        168.83 [deg]   Sun_angle= 11.8 [hr] (West of Sun)
MOON_POSTN:      225.29d {+15h 01m 09s}  -22.10d {-22d 06' 17"}
MOON_DIST:         6.93 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      337.33, 24.87 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      233.66, -9.97 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.

GCN NOTICE

TITLE:        GCN/SIMBAD_NED NOTICE
NOTICE_DATE:  Sat May  9 05:11:03 UTC 2009
NOTICE_TYPE:  Swift-BAT Position search
TRIGGER_NUM:  351525
RA:           241.4035 (J2000)
DEC:          -28.4037 (J2000)
 
SIMBAD search for BAT_RA,Dec=241.4035,-28.4037,radius=10.0arcmin
 
Num   RA         Dec                    Name                        Type  Num_Pub  Distance

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 09 May 09 05:10:55 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     351525,   Seg_Num: 0
GRB_RA:          241.404d {+16h 05m 37s} (J2000),
                 241.548d {+16h 06m 12s} (current),
                 240.632d {+16h 02m 32s} (1950)
GRB_DEC:         -28.404d {-28d 24' 12"} (J2000),
                 -28.429d {-28d 25' 42"} (current),
                 -28.269d {-28d 16' 07"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       28610 [cnts]    Image_Peak=353 [image_cnts]
TRIGGER_DUR:     8.192 [sec] 
TRIGGER_INDEX:   490     E_range: 50-350 keV
BKG_INTEN:       196468 [cnts]
BKG_TIME:        18515.27 SOD {05:08:35.27} UT
BKG_DUR:         64 [sec]
GRB_DATE:        14960 TJD;   129 DOY;   09/05/09
GRB_TIME:        18603.59 SOD {05:10:03.59} UT
GRB_PHI:          60.51 [deg]
GRB_THETA:        32.59 [deg]
SOLN_STATUS:     0x20000003
RATE_SIGNIF:     16.03 [sigma]
IMAGE_SIGNIF:    7.05 [sigma]
MERIT_PARAMS:     +1  +0  +0  +3  +3  -3  -5  +0 +95  +0 
SUN_POSTN:        46.26d {+03h 05m 03s}  +17.39d {+17d 23' 30"}
SUN_DIST:        162.14 [deg]   Sun_angle= 11.0 [hr] (West of Sun)
MOON_POSTN:      225.28d {+15h 01m 08s}  -22.10d {-22d 06' 12"}
MOON_DIST:        15.99 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      346.67, 17.54 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      244.88, -7.42 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Coordinates.  
COMMENTS:        This is a rate trigger.  
COMMENTS:        A point_source was found.  
COMMENTS:        This does not match any source in the on-board catalog.  
COMMENTS:        This does not match any source in the ground catalog.  
COMMENTS:        This is a GRB.  
COMMENTS:        This trigger occurred at longitude,latitude = 8.81,-9.13 [deg].  
COMMENTS:           
COMMENTS:        NOTE: This BAT event is temporally(2.0<100sec) coincident with the FERMI_LAT event (trignum=263538607).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Sat 09 May 09 05:13:38 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     351525,   Seg_Num: 0
GRB_RA:          241.404d {+16h 05m 37s} (J2000),
                 241.548d {+16h 06m 12s} (current),
                 240.632d {+16h 02m 32s} (1950)
GRB_DEC:         -28.404d {-28d 24' 12"} (J2000),
                 -28.429d {-28d 25' 42"} (current),
                 -28.269d {-28d 16' 07"} (1950)
GRB_DATE:        14960 TJD;   129 DOY;   09/05/09
GRB_TIME:        18603.59 SOD {05:10:03.59} UT
TRIGGER_INDEX:   490
GRB_PHI:          60.51 [deg]
GRB_THETA:        32.59 [deg]
DELTA_TIME:      -31.00 [sec]
TRIGGER_DUR:     8.192 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     16.03 [sigma]
IMAGE_SIGNIF:    7.05 [sigma]
LC_URL:          sw00351525000msb.lc
SUN_POSTN:        46.26d {+03h 05m 03s}  +17.39d {+17d 23' 32"}
SUN_DIST:        162.14 [deg]   Sun_angle= 11.0 [hr] (West of Sun)
MOON_POSTN:      225.31d {+15h 01m 13s}  -22.11d {-22d 06' 34"}
MOON_DIST:        15.97 [deg]
MOON_ILLUM:      100 [%]
GAL_COORDS:      346.67, 17.54 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      244.88, -7.42 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Lightcurve.  
COMMENTS:           
COMMENTS:        The next comments were copied from the BAT_POS Notice:  
COMMENTS:        This is a rate trigger.  
COMMENTS:        A point_source was found.  
COMMENTS:        This does not match any source in the on-board catalog.  
COMMENTS:        This does not match any source in the ground catalog.  
COMMENTS:        This is a GRB.  
COMMENTS:        This trigger occurred at longitude,latitude = 8.81,-9.13 [deg].

GCN Circular #9325
D. Grupe (PSU), S. D. Barthelmy (GSFC), M. M. Chester (PSU), H. A. Krimm (CRESST/GSFC/USRA), F. E. Marshall (NASA/GSFC), D. M. Palmer (LANL), J. L. Racusin (PSU) and M. H. Siegel (PSU) report on behalf of the Swift Team:
At 05:10:03 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 090509 (trigger=351525). Swift did not slew to this burst. The BAT on-board calculated location is RA, Dec 241.404, -28.404 which is
```
   RA(J2000)  =  16h 05m 37s
   Dec(J2000) = -28d 24' 12"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows multiple peaks with a duration of about 30 sec. The peak count rate was ~1300 counts/sec (15-350 keV), at ~20 sec after the trigger.
Due to the Moon observing constraint, Swift cannot slew to the BAT position until May 12. There will thus be no XRT or UVOT data for this trigger.
Burst Advocate for this burst is D. Grupe (grupe AT astro.psu.edu). Please contact the BA by email if you require additional information regarding Swift followup of this burst. In extremely urgent cases, after trying the Burst Advocate, you can contact the Swift PI by phone (see Swift TOO web site for information: http://www.swift.psu.edu/too.html.)
GCN Circular #9326
F. Olivares, J. Greiner, T. Kruehler (all MPE Garching) and S. Klose (TLS) report on behalf of the GROND team:
We observed the field of GRB 090509 (Swift trigger 351525; Grupe et al., GCN #9325) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2 m ESO/MPI telescope at La Silla Observatory (Chile).
We detect a bright uncatalogued source in all bands at
16:05:39.01 -28:23:59.7
with a magnitude of r' = 17.9 at 15 min after the burst, calibrated using the GROND zeropoint.
GCN Circular #9327
S. Covino, P. D'Avanzo, L.A. Antonelli, D. Malesani, D. Fugazza, L. Calzoletti, S. Campana, G. Chincarini, M.L. Conciatore, S. Cutini, V. D'Elia, F. D'Alessio, F. Fiore, P. Goldoni, D. Guetta, C. Guidorzi, G.L. Israel, E. Maiorano, N. Masetti, A. Melandri, E.J.A. Meurs, L. Nicastro, E. Palazzi, E. Pian, S. Piranomonte, L. Stella, G. Stratta, G. Tagliaferri, G. Tosti, V. Testa, S.D. Vergani, F. Vitali report on behalf of the REM team:
The robotic 60-cm REM telescope located at La Silla (Chile) observed automatically the field of the GRB 090509 (Grupe et al. GCN9325) starting about 3min after the burst. We detect a fading object in the BAT error circle in our first H-band images at R~14.3 at coordinates: RA(J2000) 16:05:38.99; Dec(J2000) -28:23:58.7 with 1 arcsec error. Moon is only at about 15 deg preventing useful optical observations.
GCN Circular #9328
F. Olivares, T. Kruehler (MPE Garching), S. Klose (Tautenburg), and J. Greiner (MPE Garching) report on behalf of the GROND team:
In addition to our previous GCN (Olivares et al., GCN #9326) we report here the observed preliminary magnitudes (in the AB system) for the afterglow (GCN #9326 and Covino et al., GCN #9327) of GRB 090509 (Grupe et al., GCN #9325). Based on 8 min of effective exposure starting at 5:22 UT (12 minutes after the trigger), we measure
```
g = 18.12 +/- 0.01
r = 17.75 +/- 0.01
i = 17.48 +/- 0.01
z = 17.22 +/- 0.01
J = 16.87 +/- 0.07
H = 16.57 +/- 0.12
K = 16.31 +/- 0.17
```
The quoted error is statistical only. There is an additional systematic error from the calibration against the GROND zeropoints and 2MASS field stars which is expected to be in the 0.1 mag range.
After correcting for a Galactic foreground extinction corresponding to a reddening of E_(B-V)=0.206 mag (Schlegel et al.), the g' to K band is well described with a single power law. This implies, that Lyman alpha is below or very close to the blue edge of the g' band, and constrains the redshift to smaller than z < 3.0 (90% confidence limit).
GCN Circular #9333
B. E. Cobb (UC Berkeley) reports:
Using the ANDICAM instrument on the 1.3m telescope at CTIO, we obtained optical/IR imaging of the error region of GRB 090509 (Grupe et al. GCN 9325) beginning approximately 0.8 hours post-burst (2009-05-09 05:59 UT). Several dithered images were obtained in each filter, with total summed exposure times of 180s in each of BRIJK and 120s in each of H and V.
The GRB afterglow (Olivares et al. GCN 9326, Covino et al. GCN 9327) is detected in all filters with the following magnitudes at a mid-exposure time of 2009-05-09 06:14 UT (1.07 hours post-burst):
```
B= 20.18 +/- 0.13
V= 19.68 +/- 0.16
R= 19.02 +/- 0.10
I= 18.76 +/- 0.09
J= 17.70 +/- 0.16
H= 17.07 +/- 0.15
K= 16.48 +/- 0.22
```
(Optical photometry is calibrated against Landolt standard stars and IR photometry is calibrated against 2MASS stars in the field.)
GCN Circular #9335
J. Tueller (GSFC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), D. Grupe (PSU), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL), A. M. Parsons (GSFC), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (GSFC/ORAU), T. N. Ukwatta (GWU) (i.e. the Swift-BAT team):
Using the data set from T-60 to T+243 sec from the recent telemetry downlink, we report further analysis of BAT GRB 090509 (trigger #351525) (Grupe, et al., GCN Circ. 9325). The BAT ground-calculated position is RA, Dec = 241.426, -28.420 deg, which is
```
   RA(J2000)  =  16h 05m 42.3s 
   Dec(J2000) = -28d 25' 12.6" 
```
with an uncertainty of 1.9 arcmin, (radius, sys+stat, 90% containment). The partial coding was 29%.
The mask-weighted light curve shows multiple overlapping peaks starting at ~T-4 sec, peaking at ~T+21 sec, and ending at ~T=3 sec. T90 (15-350 keV) is 20.4 +- 1.7 sec (estimated error including systematics).
The time-averaged spectrum from T-1.1 to T+22.4 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.54 +- 0.16. The fluence in the 15-150 keV band is 1.1 +- 0.1 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+20.73 sec in the 15-150 keV band is 1.5 +- 0.3 ph/cm2/sec. All the quoted errors are at the 90% confidence level.
The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/351525/BA/
GCN Circular #9349
H. A. Krimm (GSFC/USRA), S. D. Barthelmy (GSFC), and J. R. Cummings (GSFC/UMBC) for the Swift-BAT team.
Here we report on further analysis of GRB 090509 (Grupe et al., GCN Circ. 9325)based on additional event data received since GCN Circ. 9335 (Tueller et al.) was issued. The results given here supersede those from GCN Circ. 9335.
Using the data set from T-239 to T+316 sec from the recent telemetry downlink, we report further analysis of BAT GRB 090509 (trigger #351525). The BAT ground-calculated position is RA, Dec = 241.422, -28.385 deg which is
```
    RA(J2000)  =  16h 05m 41.3s
    Dec(J2000) = -28d 23' 04.4"
```
with an uncertainty of 2.1 arcmin, (radius, sys+stat, 90% containment). The partial coding was 29%.
The mask weighted light curve consists of two sets of peaks widely separated in time. The first complex contains multiple overlapping peaks starting at ~T-4 sec, peaking at ~T+21 sec, and ending at ~T+40 sec. The second complex also contains multiple overlapping peaks starting at ~T+240 sec, peaking at ~T+250 sec and continuing until at least ~T+300 sec, when a pre-planned slew caused the source to move out of the BAT field of view. However until ~T+950 sec the source was at a location outside the field of view where high energy (> 50 keV) photons from the source could have penetrated the BAT shield and contributed tothe non-maskweighted light curve. Examination of the raw light curve shows no additional peaks comparable in intensity to those described above. We cannot rule out weak source activity or activity below about 50 keV. Based on the available data, T90 (15-350 keV) is 335 +- 32 sec (estimated error including systematics).
The time-averaged spectrum from T-62.6 to T+298.7 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.75 +- 0.20. The fluence in the 15-150 keV band is 3.3 +- 0.4 x 10-6 erg/cm2. The 1-sec peak photon flux measured from T+20.73 sec in the 15-150 keV band is 1.5 +- 0.3 ph/cm2/sec. All the quoted errors are at the 90% confidence level.
The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/351525/BA/
GCN Report 216.1
GCN_Report 216.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_216_1.pdf by D. Gruppe at PSU titled: "Final Results on Swift GRB 090509"
GCN Circular #9363
```
SUBJECT: GRB 090509 - Zadko Telescope observations
FROM: D.M Coward at UWA
```
Liang Yan and A. Imerito report on behalf of the Zadko Telescope Team:
D.M. Coward, Liang Yan, A. Imerito, T.P. Vaalsta, A. Ahmet, J. Zadko, D. Blair, R. Burman, P. Luckas, S. Gordon, K. Frost, A. Fletcher, J. Moore (University of Western Australia) M. Todd, M. Zadnik (Curtin University) M. Boer, A. Klotz (TAROT)
The 1 m Zadko Telescope team observed the field of GRB 090509 (trigger=351525, D. Grupe et al. GCN 9325) 8hr after the Swift trigger.
We stacked 48x5s unfiltered images of the field from 13:10:32 to 13:24:16 UT (2009-05-09)
No candidate afterglow was observed at the GROND position (GCN 9326) nor at the BAT-refined position (GCN 9349), down to an Rmag of approx. 17.6. (The OA magnitude limit was estimated by comparing nearby USNO-B1 reference stars.)
The Zadko Telescope is currently being commissioned. This message is quotable in publications
```
Dr David Coward
Senior Research Fellow
School of Physics
University of Western Australia
Crawley WA 6009

Tel: +61 8 6488 4563
Mobile 0423981240
Fax: +61 8 6488 1170
```
GCN Circular #9366
A. von Kienlin (MPE) and Sheila McBreen (UCD/MPE) report on behalf of the Fermi GBM Team:
"At 05:10:05.72 UT on 09 May 2009, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 090509 (trigger 263538607 / 090509215) which was also detected by the SWIFT-BAT (Grupe et al. 2008, GCN 9325; Krimm et al., GCN 9349). The GBM on-ground location is consistent with the Swift position.
The angle from the Fermi LAT boresight is 75 degrees.
The GBM light curve consists of two widely separated multi-peaked emission periods with a duration (T90) of about 295 s (8-1000 keV). The time-averaged spectrum of the first emission complex from T0-3.072 to T0+24.576 s is well fit by a power law function with an exponential high energy cutoff. The power law index is -0.90 +/- 0.16 and the cutoff energy, parameterized as Epeak, is 343 +/- 93 keV (chi squared 375 for 360 d.o.f.). The time-averaged spectrum of the second emission complex from T0+239.619 s to T0+288.772 s is best fit by a simple power law function with index -1.55 +/- 0.07 (chi squared 328 for 361 d.o.f.).
The summed event fluence (8-1000 keV) of both time intervals is (8.4 +/- 0.4)E-06 erg/cm^2. The 1-sec peak photon flux measured starting from T0+18.432 s in the 8-1000 keV band is 3.1 +/- 0.3 ph/s/cm^2.
The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."

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Jochen Greiner, last update: 15-May-2009 [Disclaimer]