Gamma-ray Burst 061122

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:          GCN/INTEGRAL NOTICE
NOTICE_DATE:    Wed 22 Nov 06 07:57:25 UT
NOTICE_TYPE:    INTEGRAL Wakeup
TRIGGER_NUM:    3532,   Sub_Num: 0
GRB_RA:         303.8345d {+20h 15m 20s} (J2000),
                303.9139d {+20h 15m 39s} (current),
                303.2579d {+20h 13m 02s} (1950)
GRB_DEC:        +15.4953d {+15d 29' 43"} (J2000),
                +15.5167d {+15d 31' 00"} (current),
                +15.3415d {+15d 20' 29"} (1950)
GRB_ERROR:      2.68 [arcmin, radius, statistical only]
GRB_INTEN:      17.42 [sigma]
GRB_TIME:       28610.17 SOD {07:56:50.17} UT
GRB_DATE:       14061 TJD;   326 DOY;   06/11/22
SC_RA:          296.74 [deg] (J2000)
SC_DEC:          17.98 [deg] (J2000)
SUN_POSTN:      237.68d {+15h 50m 44s}  -20.12d {-20d 07' 17"}
SUN_DIST:        74.18 [deg]   Sun_angle= -4.4 [hr] (East of Sun)
MOON_POSTN:     254.62d {+16h 58m 28s}  -27.71d {-27d 42' 32"}
MOON_DIST:       64.41 [deg]
GAL_COORDS:      56.64,-10.67 [deg] galactic lon,lat of the burst
ECL_COORDS:     310.50, 34.30 [deg] ecliptic lon,lat of the burst
COMMENTS:       INTEGRAL GRB Coordinates.
COMMENTS:       Possibly real GRB event

GCN/BACODINE POSITION NOTICE

TITLE:          GCN/INTEGRAL NOTICE
NOTICE_DATE:    Wed 22 Nov 06 08:00:26 UT
NOTICE_TYPE:    INTEGRAL Refined
TRIGGER_NUM:    3532,   Sub_Num: 1
GRB_RA:         303.8379d {+20h 15m 21s} (J2000),
                303.9173d {+20h 15m 40s} (current),
                303.2614d {+20h 13m 03s} (1950)
GRB_DEC:        +15.5140d {+15d 30' 50"} (J2000),
                +15.5354d {+15d 32' 07"} (current),
                +15.3602d {+15d 21' 37"} (1950)
GRB_ERROR:      2.55 [arcmin, radius, statistical only]
GRB_INTEN:      34.45 [sigma]
GRB_TIME:       28621.81 SOD {07:57:01.81} UT
GRB_DATE:       14061 TJD;   326 DOY;   06/11/22
SC_RA:          296.74 [deg] (J2000)
SC_DEC:          17.98 [deg] (J2000)
SUN_POSTN:      237.69d {+15h 50m 45s}  -20.12d {-20d 07' 19"}
SUN_DIST:        74.19 [deg]   Sun_angle= -4.4 [hr] (East of Sun)
MOON_POSTN:     254.65d {+16h 58m 35s}  -27.71d {-27d 42' 43"}
MOON_DIST:       64.41 [deg]
GAL_COORDS:      56.65,-10.66 [deg] galactic lon,lat of the burst
ECL_COORDS:     310.51, 34.32 [deg] ecliptic lon,lat of the burst
COMMENTS:       INTEGRAL GRB Coordinates.  
COMMENTS:       Possibly real GRB event

red DSS finding chart ps-file

GCN NOTICE

TITLE:          GCN/INTEGRAL NOTICE
NOTICE_DATE:    Wed 22 Nov 06 09:04:43 UT
NOTICE_TYPE:    INTEGRAL Offline
TRIGGER_NUM:    3532,   Sub_Num: 2
GRB_RA:         303.8370d {+20h 15m 21s} (J2000),
                303.9164d {+20h 15m 40s} (current),
                303.2605d {+20h 13m 03s} (1950)
GRB_DEC:        +15.5139d {+15d 30' 50"} (J2000),
                +15.5353d {+15d 32' 07"} (current),
                +15.3601d {+15d 21' 36"} (1950)
GRB_ERROR:      2.00 [arcmin, radius, statistical only]
GRB_INTEN:      34.45 [sigma]
GRB_TIME:       28621.81 SOD {07:57:01.81} UT
GRB_DATE:       14061 TJD;   326 DOY;   06/11/22
SC_RA:          296.74 [deg] (J2000)
SC_DEC:          17.98 [deg] (J2000)
SUN_POSTN:      237.73d {+15h 50m 56s}  -20.13d {-20d 07' 53"}
SUN_DIST:        74.15 [deg]   Sun_angle= -4.4 [hr] (East of Sun)
MOON_POSTN:     255.29d {+17h 01m 09s}  -27.78d {-27d 46' 41"}
MOON_DIST:       63.99 [deg]
GAL_COORDS:      56.65,-10.66 [deg] galactic lon,lat of the burst
ECL_COORDS:     310.51, 34.32 [deg] ecliptic lon,lat of the burst
COMMENTS:       INTEGRAL GRB Coordinates.  
COMMENTS:       refined_coordinates_after_offline_analysis

GCN Circular #5834
S.Mereghetti, A.Paizis (IASF-Milano), D.Gotz (CEA-Saclay), D.Petry, N.Mowlavi, M. Beck (ISDC, Versoix), and J. Borkowski (CAMK, Torun) on behalf of the IBAS Localization Team report:
A bright GRB lasting about 20 s has been detected by IBAS in IBIS/ISGRI data at 07:56:45 on November 22, 2006
```
The coordinates (J2000)  are:
RA: 303.8370 [degrees]
DEC: 15.5141 [degrees]
```
with an uncertainty of 2 arcmin (90% c.l.).
The light curve is affected by gaps due to telemetry saturation.
A plot of the light curve will be posted at
http://ibas.mi.iasf.cnr.it/IBAS_Results.html
This message can be cited.
GCN Circular #5836
S.Mereghetti (IASF-Milano), D.Gotz (CEA-Saclay) on behalf of the IBAS Localization Team report:
Analysis of the INTEGRAL/IBIS data of GRB 061122 (GCN 5834) indicates that the peak flux in the 20-200 keV range is larger than 11 ph/cmq/s (1-s integration time) and the fluence over the same energy range is larger than 3x10e-6 erg/cmq.
This message can be cited.
GCN Circular #5841
S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, and T. Cline on behalf of the Konus-Wind team report:
The long bright GRB 061122 (Mereghetti et al., GCN 5834, 5836) triggered Konus-Wind at 28608.132 s UT (07:56:48.132).
As observed by Konus-Wind it had a duration of ~10 s, fluence 2.31(-0.12, +0.05)x10^-5 erg/cm2, the 64-ms peak flux measured from T0+3.104 s 8.81(-1.05, +0.83)x10^-6 erg/cm2/s (both in the 20 keV - 2 MeV energy range).
The time-integrated spectrum of the GRB (from T0 to T0+12.032 s) is well fitted (in the 20 keV - 2 MeV range) by a power law with exponential cutoff model: dN/dE ~ E^(-alpha) * exp(-(2-alpha)*E/Ep) with alpha = 1.03 (-0.07, +0.06) and Ep = 160 (-7, +8) keV (chi2 = 64/62 dof). The fitting by GRBM (band) model yields only an upper limit on high energy photon index: beta < -3.31.
All the quoted errors are at the 90% confidence level.
The Konus-Wind light curve of this GRB is available at http://www.ioffe.rssi.ru/LEA/GRBs/GRB061122_T28608/
GCN Circular #5842
A. P. Beardmore, P. A. Evans, K. L. Page (U Leicester), S. McBreen (MPE) and D. N. Burrows (PSU) report on behalf of the Swift-XRT team:
The Swift-XRT began observing the field containing the INTEGRAL burst GRB 061122 (Mereghetti et al., GCN 5834) at 2006-11-22 14:44 UT, 24.67 ks after the trigger. In two orbits of Photon Counting mode data totalling 2.35 ks we detect an uncatalogued source at
```
RA(J2000)  =  20h 15m 19.80s
Dec(J2000) = +15d 31' 03.0"
```
with an uncertainty of 4.0 arcsec (90% containment, using the updated boresight file described by Burrows et al. in GCN Circ. 5750). This is 19.8 arcsec from the initial position reported in GCN 5834, and within the error circle.
The source is presently at an XRT count rate of 0.065 count/s, but at this stage of the observation it is impossible to say if it is fading.
This circular is an official product of the Swift-XRT team.
GCN Circular #5846
S. R. Oates (UCL-MSSL) & S. McBreen (MPE) report on behalf of the Swift UVOT team.
The Swift/UVOT began observing the field of GRB 061122 at 14:47:46 UT on November 22, 2006, around ~7 hours after the INTEGRAL trigger (Mereghetti et al., GCN 5831). We do not find any source in the co-added UVOT observations within the error circle of the XRT (Beardmore et al., GCN 5842).
Following are the 3-sigma magnitude upper limits:
```
Filter  T_start T_end  Exposure   3 sigma UL
-------------------------------------------
V       24658   58558    2645     20.69
B       25401   42918    936      20.62
U       25215   42901    1013     20.2
UVW1    25029   59414    1770     19.46
UVM2    24844   58920    2578     20.96
UVW2    24472   58124    2648     21.54
-------------------------------------------
```
T_start and T_stop are calculated from the time of the burst. The upper limits are not corrected for Galactic extinction E(B-V) = 0.183 mag.
GCN Circular #5849
J. P. Halpern & E. Armstrong (Columbia U.) report on behalf of the MDM Observatory GRB follow-up team:
"We obtained R-band observations of the field of INTEGRAL GRB 061122 (Mereghetti et al., GCN 5834) on two consecutive nights using the MDM 2.4m telescope. Within 1" of the Swift XRT candidate X-ray afterglow (Beardmore et al., GCN 5842), we find a fading object at
(J2000) R.A.=20h15m19.84s, Decl.=+15d31'02.5"
with positional uncertainty ~0.5", and the following magnitudes:
```
    ------------------------------------------------
     Date(UT)  Mid-time(UT)  t-t0(hr)   R(mag) +/-
    ------------------------------------------------
     Nov. 23      01:52       17.9      22.61  0.05
     Nov. 24      02:26       42.5      23.41  0.15
    ------------------------------------------------
```
We propose this as the optical afterglow of GRB 061122.
Magnitudes are referenced to the USNO B1.0 star at (J2000) R.A.=20h15m18.48s, Decl.= +15d31'05.5" with R=17.61, and are not corrected for Galactic extinction, A_R=0.49 mag in this direction (Schlegel et al. 1998).
MDM images of the field are posted at
http://www.astro.columbia.edu/~jules/grb/061122/
This message may be cited."
GCN Circular #5852
Jules Halpern reports:
In follow-up Swift XRT observations of INTEGRAL GRB 061122 (Mereghetti et al., GCN 5834,5836) the X-ray source reported by Beardmore et al. (GCN 5842) as having 0.065 counts/s at 7 hr after the burst, has faded to 0.0047 counts/s averaged over the interval 18-55 hr post burst. Therefore, I regard this as confirmation of the X-ray afterglow as well as the coincident optical afterglow reported in GCN 5849.
GCN Report 17.1
GCN_Report 17.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_17_1.pdf by S. McBreen at MPE titled: "Updated Swift Observations of GRB 061122"
GCN Circular #5879
K. Kinugasa (Gunma Astronomical Observatory) and K. Torii (Osaka U.) report:
The error region of INTEGRAL GRB 061122 (Mereghetti et al. GCN 5834) was imaged by the robotic 0.25m GETS telescope in the Gunma Astronomical Observatory. Unfiltered imaging started at 08:46:33 UT (49.1 minutes after the trigger) after the end of twilight.
We did not detect the optical afterglow (Halpern et al. GCN 5849) and the following 3-sigma upper limits are derived relative to USNO-A2.0 R mag.
```
------------------------------------------
StartUT  EndUT    Limit  Exposure
------------------------------------------
08:46:33 09:01:33 >15.5  30s x 20
------------------------------------------
```
1303.4186 from 19 Mar 13
D. Gotz et al.: The polarized Gamma-Ray Burst GRB 061122
We report on the polarization measure, obtained with IBIS on board INTEGRAL, of the prompt emission of GRB 061122. Over an 8 s interval containing the brightest part of the Gamma-Ray Burst we put a lower limit on its polarization fraction of 60% at 68% c.l. and of 33% at 90% c.l. on the 250-800 keV energy range. We performed late time optical and near infra-red imaging observations of the GRB field using the Telescopio Nazionale Galileo (TNG), and the Canada-France-Hawaii Telescope (CFHT). Our multi-band (ugrizYJHK) photometry allowed us to identify the host galaxy of GRB 061122 and to build its SED. Using a photometric redshift code we fitted these data, and derived the basic properties of the galaxy, including its type and redshift, that we could constrain to the interval [0.57, 2.10] at a 90% c.l., with a best fit value of z=1.33. The polarization measurement in different energy bands, together with the distance determination, allowed us to put the most stringent limit (xi < 3.4x10-16) to date to a possible Lorentz Invariance Violation based on the vacuum birefringence effect, predicted by some quantum-gravity theories.

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Jochen Greiner, last update: 19-Mar-2013 [Disclaimer]