Skip to main content
New! Browse Circulars by Event, Advanced Search, Sample Codes, Schema Release. See news and announcements

GRB 110422A

GCN Circular 11957

Subject
GRB 110422A: Swift detection of a burst
Date
2011-04-22T16:04:43Z (14 years ago)
From
Vanessa Mangano at INAF-IASFPA <vanessa@ifc.inaf.it>
V. Mangano (INAF-IASFPA), D. N. Burrows (PSU), V. D'Elia (ASDC),
N. Gehrels (NASA/GSFC), J. M. Gelbord (PSU), B. Gendre (ASDC),
S. T. Holland (CRESST/USRA/GSFC), E. A. Hoversten (PSU),
J. A. Kennea (PSU), H. A. Krimm (CRESST/GSFC/USRA),
C. B. Markwardt (NASA/GSFC), F. E. Marshall (NASA/GSFC),
D. M. Palmer (LANL), P. Romano (INAF-IASFPA),
B. Sbarufatti (INAF-OAB/IASFPA), M. H. Siegel (PSU) and
C. A. Swenson (PSU) report on behalf of the Swift Team:

At 15:41:55 UT, the Swift Burst Alert Telescope (BAT) triggered and
located the bright GRB 110422A (trigger=451901).  Swift slewed to 
the burst after a 12 minute observing constraint delay. 
The BAT on-board calculated location is 
RA, Dec 111.995, +75.106 which is 
   RA(J2000) = 07h 27m 59s
   Dec(J2000) = +75d 06' 21"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a complex peak
structure with a duration of about 50 sec.  The peak count rate
was ~24000 counts/sec (15-350 keV), at ~8 sec after the trigger. 

The XRT began observing the field at 15:55:30.4 UT, 814.5 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 112.0580, +75.1077 which is equivalent to:
   RA(J2000)  = 07h 28m 13.92s
   Dec(J2000) = +75d 06' 27.7"
with an uncertainty of 6.1 arcseconds (radius, 90% containment). This
location is 58 arcseconds from the BAT onboard position, within the BAT
error circle. No event data are yet available to determine the column
density using X-ray spectroscopy. 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 821 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers none of
the XRT error circle. The 8'x8' region for the list of sources generated
on-board covers 100% of the XRT error circle. The list of sources is typically
complete to about 18 mag. No correction has been made for the expected
extinction corresponding to E(B-V) of 0.03. 

Burst Advocate for this burst is V. Mangano (vanessa AT ifc.inaf.it). 
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 11958

Subject
GRB 110422A: Mondy optical observations
Date
2011-04-22T17:25:29Z (14 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
E. Klunko (ISTP), A. Pozanenko (IKI)  on behalf of  larger GRB follow up 
collaboration report:

We started observation of the field of GRB 110422A (Mangano  et al. GCN 
11957) with AZT-33IK on Apr. 22 (UT) 15:58.    We detected new object, not 
presented in DSS2 in coordinates (J2000) 07 28 10.972 +75 06 24.87 with 
statistical uncertainty of 1" in booth coordinates. The object is close to 
the current XRT position. The first image was unfiltered, while after 
detection we started several series in R-filter. The brightness of the 
object in the first image taken 16 min after burst onset is R=18.3 in 
comparison with nearby USNOB-1.0 field stars. We suggest that the object is 
the afterglow of GRB 110422A.
The finding chart can be found at
http://grb.rssi.ru/GRB110422A/grb110422A_AZT33IK.png
Observation is continuing. 

[GCN OPS NOTE(23apr11): Per author's request, Elunko was changed to Klunko.]

GCN Circular 11959

Subject
GRB 110422A: Swift-BAT refined analysis
Date
2011-04-22T18:14:12Z (14 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@lheamail.gsfc.nasa.gov>
D. M. Palmer (LANL), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),
V. Mangano (INAF-IASFPA), C. B. Markwardt (GSFC), T. Sakamoto (GSFC/UMBC),
M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU)
(i.e. the Swift-BAT team):
 
Using the data set from T-61 to T+195 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 110422A (trigger #451901)
(Mangano, et al., GCN Circ. 11957).  The BAT ground-calculated position is
RA, Dec = 112.057, 75.100 deg, which is 
   RA(J2000)  =  07h 28m 13.7s 
   Dec(J2000) = +75d 05' 58.8" 
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 22%.
 
The mask-weighted light curve shows several overlapping peaks starting
at ~T-15 sec, peaking at ~T+8 sec, and ending at ~T+60 sec.  At the 3-sigma
level, there is another peak from T+70 to T+115 sec.  T90 (15-350 keV)
is 25.9 +- 0.6 sec (estimated error including systematics).
 
The time-averaged spectrum from T-11.2 to T+40.3 sec is best fit by a power law
with an exponential cutoff.  This fit gives a photon index 0.86 +- 0.10, 
and Epeak of 149.4 +- 18.5 keV (chi squared 46.5 for 56 d.o.f.).  For this
model the total fluence in the 15-150 keV band is 4.1 +- 0.1 x 10^-5 erg/cm2
and the 1-sec peak flux measured from T+6.90 sec in the 15-150 keV band is
30.7 +- 1.0 ph/cm2/sec.  A fit to a simple power law gives a photon index
of 1.35 +- 0.00 (chi squared 118.3 for 57 d.o.f.).  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/451901/BA/

GCN Circular 11960

Subject
GRB 110422A: MASTER earlier OT polarization observations
Date
2011-04-22T21:09:53Z (14 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <gcncirc@observ.inetcomm.ru>
O. Gres, K.Ivanov, V.A.Poleshchuk, S.Yazev, N.M.Budnev, O.Chuvalaev
Irkutsk State University

E. Gorbovskoy, V. Lipunov, V.Kornilov, D.Kuvshinov, A.Belinski, N.Tyurina, 
N.Shatskiy, P.Balanutsa, V.V.Chazov, P.V.Kortunov, A.Kuznetsov, D.Zimnukhov, M. 
Kornilov, A.Kuznetsov, D.Zimnukhov, M. Kornilov, A.Sankovich
Sternberg Astronomical Institute, Moscow State University

A. Tlatov, A.V. Parhomenko, D. Dormidontov
Kislovodsk Solar Station of the Pulkovo Observatory

V.Krushinski, I.Zalozhnich, T.Kopytova, A. Popov
Ural State University, Kourovka

V.Yurkov, Yu.Sergienko, D.Varda, I.Kudelina
Blagoveschensk Educational State University, Blagoveschensk

  MASTER II  robotic telescope (MASTER-Net: http://observ.pereplet.ru)
located in Tunka (Baykal lake) was pointed to the  GRB 110422A 34 sec 
after notice time and 53 sec after GRB time at 2011-04-22 15:42:48.507 UT. 
On our first (10s exposure) double  set we  found optical transient 
within SWIFT error-box (Palmer et al.11959). The position coincided with 
Elunko et al. GCN 11958.
The polarizated magnitude in R band is  ~16.5+-0.4 .
We see  OT on all next images in both polarizations.
Is seems some brightenning during first minutes.
The reduction is continuated.
  The message may be cited.

GCN Circular 11961

Subject
GRB 110422A: NOT optical observation
Date
2011-04-22T22:19:20Z (14 years ago)
From
Dong Xu at Weizmann Inst <dong.xu@weizmann.ac.il>
Dong Xu (WIS), Anders Thygesen, Fatemeh Kiaee (NOT), and Pall
Jakobsson (U. Iceland) report on behalf of a large collaboration:

We observed the field of GRB 110422A (Mangano  et al., GCN 11957) at
the Nordic Optical Telescope (NOT) equipped with ALFOSC. We obtained
2x300 s R-band images with a median time 21:11:33.3 UT (i.e., 5.49397
hr after the BAT trigger). The images, with an airmass ~1.5,  were
taken under the windy condition.

A new optical source is detected at coordinates

(RA,Dec)(J2000.0) = (07:28:11.06, +75:06:25.00)
(error-radius:  ~ 0.1 arcsec),

being consistent with the finding in Elunko et al. (GCN 11958) and
Gres et al. (GCN 11960). Note that this position is southwest of and
outside the XRT error circle reported at http://www.swift.ac.uk/sper/.
The source has R~20.0 mag, calibrated with the #1651-0050630 star
(R1=19.08) in the USNO B1 catalog.

Further observation is planned as long as the weather could stay
observable at La Palma.

GCN Circular 11962

Subject
GRB 110422A: SAO RAS optical observations
Date
2011-04-22T23:53:33Z (14 years ago)
From
Vladimir Sokolov at SAO RAS <sokolov@sao.ru>
A. S. Moskvitin (SAO RAS, Niznijh Arkhyz, Russia), report:

The field of GRB 110422A (Mangano  et al., GCN 11957) were observed
with the Zeiss-1000 telescope of SAO RAS, Russia. The observations
were carried out in the B and Rc bands at 18:39:11 -- 19:00:08 UT,
April, 22 (~3 hours after the trigger).

The magnitude of OT (Elunko et al. GCN 11958, Gres et al. GCN 11960
and Xu et al. GCN 11961) were measured as R = 19.13 +/- 0.13 in
comparison with nearby USNO-B1.0 stars (R2 magnitudes).

The message may be cited.

GCN Circular 11963

Subject
GRB 110422A: TNG optical observations
Date
2011-04-23T00:25:49Z (14 years ago)
From
Andrea Melandri at Liverpool John Moores U <axm@astro.livjm.ac.uk>
A. Melandri, P. D'avanzo, D. Fugazza (INAF-OAB) and E. Palazzi (INAF-IASFBo)
on behalf of a larger collaboration report:

We observed the field of GRB 110422A (Mangano et al. GCN 11957) with the 3.6m
TNG equipped with the Dolores camera. Few sets of unfiltered images were acquired
starting on Apr 22.89 UT (i.e. ~5.7 hours after the burst event).

The optical afterglow (Elunko et al. GCN 11958; Gres et al. GCN 11960;  Xu et al.
GCN 11961, Moskvitin GCN 11962) is clearly detected in all our frames. The observed
magnitudes (calibrated with respect to the same star used in GCN 11961) are

Dt_start  t_exp    R_mag   err
   [hr]            [s]
---------------------------------------------
  5.777      60.0    20.17   0.03
  5.934      60.0    20.24   0.05
  5.998      60.0    20.03   0.05
  8.052      60.0    20.24   0.04

Our observations, coupled with previous observations reported on GCNs imply a
power-law decay index for the optical afterglow of ~0.55.

Further observations are ongoing.

We thank the TNG staff for their support, in particular Massimo Cecconi
and Giovanni Mainella.

[GCN OPS NOTE(23apr11): Per author's request, the last sentence was added.]

GCN Circular 11964

Subject
GRB 110422A: correction to the GCN circ. 11958
Date
2011-04-23T00:35:18Z (14 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
A. Pozanenko (IKI) report:

In the GCN circ. 11958 due to misprint the author's name is spelled 
incorrectly. The names of the author's of the GCN circ. 11958 should be read 
as follows:

E. Klunko (ISTP), A. Pozanenko (IKI)

I apologize for possible inconvenience.

GCN Circular 11965

Subject
GRB 110422A: Enhanced Swift-XRT position
Date
2011-04-23T04:00:39Z (14 years ago)
From
Phil Evans at U of Leicester <pae9@star.le.ac.uk>
P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 1328 s of XRT Photon Counting mode data and 3 UVOT
images for GRB 110422A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 112.04671, +75.10666 which is equivalent
to:

RA (J2000): 07h 28m 11.21s
Dec (J2000): +75d 06' 24.0"

with an uncertainty of 1.7 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.

GCN Circular 11966

Subject
GRB 110422A: THO optical observations
Date
2011-04-23T04:09:32Z (14 years ago)
From
Veli-Pekka Hentunen at Taurus Hill Obs,A95 <veli-pekka.hentunen@kassiopeia.net>
Veli-Pekka Hentunen, Markku Nissinen and Tuomo Salmi (Taurus Hill
Observatory, Varkaus, Finland) report:

Taurus Hill Observatory's (A95) Celestron C-14 (OTA) telescope 14"
FL 3910 mm with NextGEN 0.5X optical reducer and SBIG ST-8XME 
camera were used to detect GRB 110422A optical afterglow. The 
observations were started at 2011-04-22 20:26:30 (UT) and stopped at 
2011-04-22 20:57:20 (UT) (~5 hours after the trigger). Six unfiltered 
observations with 300s exposure time were made. The afterglow was 
detected at following position RA 7 28 10.98 and DEC +75 06 25.4 
consistent those given by Elunko E. et al. (GCN 11958) to within positional
errors.

The following magnitudes were obtained from the observations using 
NOMAD1 1651-0051346 (R = 16.040) as the comparison:

Tmid(s)+T0  Filter          Exp (sec)     Mag      Mag err   Limit (sigma 3)
17285           unfilt          300             19.5         0.7         19.7
17535           unfilt          300             19.6         0.8         19.7
18152           unfilt          300             19.4         0.7         19.7
18462           unfilt          300             19.7         0.9         19.7

 
A png image of the 3x300sec clear filter observations is available at the 
following URL link:
http://cutenews.kassiopeia.net/data/upimages/GRB_110422A_OA_THO.png

GCN Circular 11967

Subject
GRB 110422A: CQUEAN griz Observation
Date
2011-04-23T06:42:52Z (14 years ago)
From
Yiseul Jeon at SNU/CEOU <ysjeon@astro.snu.ac.kr>
Yiseul Jeon, Myungshin Im, Won-Kee Park (CEOU/Seoul National Univ),
 Soojong Pak, Hyeongju Jeong, (Kyunghee University)

 We observed GRB 110422A (Mangano et al. GCN 11957) with griz
filters using CQUEAN camera on the 2.1m telescope at the McDonald
observatory, TX. The observation started at 2011 April 23, 02:53:11 UT,
about 11.19 hours after the BAT trigger.
 We confirm a bright afterglow in all the griz images at the location
reported earlier (Xu et al. GCN 11961; Evans et al. GCN 11965), with
a preliminary photometry of r ~ 20.36 +- 0.05  AB mag, based on the
photometric standard star data taken on the same night.
 Further analysis of the data is ongoing.

GCN Circular 11968

Subject
GRB 110422A: Swift-XRT refined Analysis
Date
2011-04-23T11:27:20Z (14 years ago)
From
Vanessa Mangano at INAF-IASFPA <vanessa@ifc.inaf.it>
V. Mangano (INAF-IASFPA) and B. Sbarufatti (INAF OAB/INAF IASFPA)
report on behalf of the Swift-XRT team:

We have analysed 3.5 ks of XRT data for GRB 110422A (Mangano  et al.
GCN Circ. 11957), from 804 s to 12.7 ks after the  BAT trigger. The
data comprise 394 s in Windowed Timing (WT) mode (the first 9 s were
taken while Swift was slewing) with the remainder in Photon Counting
(PC) mode. The enhanced XRT position for this burst was given by Evans
et al. (GCN. Circ 11965).

The light curve can be modelled with an initial power-law decay with an
index of alpha=1.02 (+/-0.03), followed by a break at T+7585 s to an
alpha of 2.2 (+0.5, -0.4).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index	of 1.99 (+/-0.09). The
best-fitting absorption column is  1.94 (+0.26, -0.24) x 10^21 cm^-2,
in excess of the Galactic value of 4.2 x 10^20 cm^-2 (Kalberla et al.
2005). The PC mode spectrum has a photon index of 2.13 (+0.11, -0.10)
and a best-fitting absorption column of 2.28 (+0.31, -0.29) x 10^21
cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum  is 3.9 x 10^-11 (6.3 x 10^-11) erg
cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:	     2.28 (+0.31, -0.29) x 10^21 cm^-2
Galactic foreground: 4.2 x 10^20 cm^-2
Excess significance: 12.8 sigma
Photon index:	     2.13 (+0.11, -0.10)

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00451901.

This circular is an official product of the Swift-XRT team.

GCN Circular 11969

Subject
GRB 110422A: Swift/UVOT Detection of optical afterglow
Date
2011-04-23T13:02:09Z (14 years ago)
From
Alice Breeveld at MSSL-UCL <aab@mssl.ucl.ac.uk>
A. A. Breeveld (MSSL-UCL) and V. Mangano (INAF-IASFPA)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 110422A
822 s after the BAT trigger (Mangano et al., GCN Circ. 11957).
An optical afterglow consistent with the optical position found by 
Klunko et al. (GCN 11958) and others is found in the UVOT, and is 
clearly fading. It is detected in initial exposures in both white and 
b, and also in v and u when the initial exposures are summed up.
Preliminary magnitudes and 3-sigma upper limits using the UVOT 
photometric system (Poole et al. 2008, MNRAS, 383, 627) for the first 
finding chart (FC) exposure and subsequent exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC           822          972          147         18.80 �� 0.12
white (summed)    1054         1766          97.2        19.5 �� 0.23
white             7837         8037          197          >20.4
v (summed)        1104         2336          156         18.72 �� 0.35
b                 1029         1049          19.4        18.02 �� 0.3
b (summed)        1202         2435          156         18.97 �� 0.22
u (summed)        1004         2410          175         18.8 �� 0.26
w1 (summed)        980         2385          175         >19.4
m2 (summed)       1128         2360          156         >19.4
w2 (summed)       1079         2310          156         >19.6

The values quoted above are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.03 in the direction of the burst
(Schlegel et al. 1998).

[GCN OPS NOTE(23apr11): Per author's request, the spelling on the Klunko
reference was corrected.]

GCN Circular 11970

Subject
GRB 110422A: Further NOT observation
Date
2011-04-23T22:23:51Z (14 years ago)
From
Dong Xu at Weizmann Inst <dong.xu@weizmann.ac.il>
D. Xu (WIS), J. P. U. Fynbo (DARK/NBI), M. Nielsen (NOT), and P.
Jakobsson (U. Iceland) report on behalf of a large collaboration:

We continued to observe the field of GRB 110422A (Mangano  et al., GCN
11957) at the Nordic Optical Telescope (NOT) equipped with ALFOSC. We
obtained 2x300 s, 3x300 s, and 3x300 s images in the R, V, and I
filters, respectively. The images, with an airmass ~1.5, were still
taken with strong wind.

The optical afterglow (Elunko et al., GCN 11958; Xu et al., GCN 11961)
has decayed to R=21.41+/-0.10 mag with a median time 21:06:08.9 UT on
April 23 (i.e., 29.4 hr after the BAT
trigger), compared with our previous measurement R=20.00+/-0.02 mag,
both calibrated with the #1651-0050630 star (R1=19.08) in the USNO B1
catalog. The observations at the two epochs indicates a power-law
decay index of ~0.8 for the R-band lightcurve.

GCN Circular 11971

Subject
Konus-Wind observation of GRB 110422A
Date
2011-04-24T09:30:07Z (14 years ago)
From
Valentin Pal'shin at Ioffe Inst <val@mail.ioffe.ru>
S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks,
P. Oleynik, M. Ulanov, D. Svinkin, and
T. Cline on behalf of the Konus-Wind team, report:

The long bright GRB 110422A (Swift-BAT trigger #451901: Mangano et al.,
GCN 11957; Palmer et al., GCN 11959) triggered Konus-Wind at
T0(KW)=56502.948 s UT (15:41:42.948).
The burst light curve shows a multipeaked structure with a
duration of ~40 s.

As observed by Konus-Wind the burst
had a fluence of (8.56 +/- 0.02)x10^-5 erg/cm2,
and a 64-ms peak flux measured from T0+18.128 s
of (1.20 +/- 0.15)x10^-5 erg/cm2/s
(both in the 20 keV - 2 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+38.656 s) can be fitted (in the 20 keV - 2 MeV
range) by the GRB (Band) model for which:
the low-energy photon index is alpha = -0.65 +/- 0.06,
the high energy photon index beta = -2.96(-0.19, +0.14),
the peak energy Ep = 152 +/- 5 keV (chi2 = 96.8/64 dof).
The spectrum at the maximum count rate
(measured from T0+17.664 to T0+18.432 s) is well fitted
(in the 20 keV - 2 MeV range) by the GRB (Band)
model, for which:
the low-energy photon index alpha = -0.53 (-0.14, +0.17),
the high energy photon index beta = -2.65 (-0.62, +0.28),
the peak energy Ep = 246(-34, +37) keV (chi2 = 55.7/48 dof).

All the quoted errors are at the 90% confidence level.

The Konus-Wind light curve of this GRB is available
at http://www.ioffe.ru/LEA/GRBs/GRB110422_T56502/

GCN Circular 11972

Subject
GRB110422A: MITSuME Ishigakijima Optical Observation
Date
2011-04-24T13:08:22Z (14 years ago)
From
Daisuke Kuroda at OAO/NAOJ <dikuroda@oao.nao.ac.jp>
D. Kuroda (OAO, NAOJ), H. Hanayama, T. Miyaji, J. Watanabe (IAO, NAOJ),
K. Yanagisawa (OAO, NAOJ), S.Nagayama (NAOJ), M. Yoshida (Hiroshima),
K. Ohta (Kyoto) and N. Kawai(Tokyo Tech)
report on behalf of the MITSuME collaboration:

We observed the field of GRB 110422A (Mangano et al., GCNC 11957)
with the optical three color (g', Rc and Ic) CCD camera attached
to the Murikabushi 1m telescope of Ishigakijima Astronomical
Observatory.

The observation started on 2011-04-23 12:44:54 UT, (~21 hours after
the burst). We detected the previously reported afterglow
(Klunko et al., GCNC 11958; Gres et al., GCNC 11960) in Rc band.

Photometric results and three sigma upper limits of the OT are
listed below. We used GSC2.3 catalog for flux calibration.


#T0+[day]  MID-UT    T-EXP[sec]   g'    Rc  Rc_err   Ic
----------------------------------------------------------------------
0.89834    13:15:32    2400.0   >21.0  20.9  0.3   >19.3
----------------------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]

[GCN OPS NOTE(24apr11): Per author's request, the "110322" was
changed to "110422A" in the first sentence.]

GCN Circular 11973

Subject
GRB 110422A: optical observations in CrAO
Date
2011-04-24T22:48:24Z (14 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
V. Rumyantsev,  K. Antoniuk (CrAO), A. Pozanenko (IKI) report on behalf of 
larger GRB  follow-up collaboration:

We observed  the field of the Swift GRB 110422A (Mangano  et al., GCN 
11957) with AZT-11 telescope of CrAO between  Apr. 22 (UT) 19:13 and  20:11. 
We clearly detect the afterglow (Klunko et al. GCN 11958, Gres et al. GCN 
11960, Xu et al. GCN 11961). The photometry is based on the USNO B1.0 star 
1651-0050626   (07 28 13.15 +75 06 51.5) assuming R=18.56 :

T0+      Filter,   Exposure, mag.
(mid, d)              (s)

0.1675  R        20x180       19.32  +/-0.08

GCN Circular 11974

Subject
GRB110422A: NOT optical follow-ups
Date
2011-04-25T21:46:49Z (14 years ago)
From
Dong Xu at Weizmann Inst <dong.xu@weizmann.ac.il>
Dong Xu (WIS), Erkki Kankare, Tuomas Kangas (U. Turku), and Pall
Jakobsson (U. Iceland) report on behalf of a large collaboration:

We continued to observe the field of GRB 110422A (Mangano et al., GCN
11957) at the Nordic Optical Telescope (NOT) equipped with ALFOSC. We
obtained 2x360 s in the R filter with some clouds and a seeing ~0.9".

The optical afterglow (Elunko et al., GCN 11958; Gres et al., GCN
11960; Xu et al., GCN 11961) has decayed to R=22.5+/-0.2 mag with a
median time 21:17:58.8 UT on April 25 (i.e., 77.6 hr after the BAT
trigger), calibrated with the #1651-0050630 star (R1=19.08) in the
USNO B1 catalog.

GCN Circular 11975

Subject
GRB 110422A: Herschel observation scheduled
Date
2011-04-25T21:51:12Z (14 years ago)
From
Dong Xu at Weizmann Inst <dong.xu@weizmann.ac.il>
Dong Xu (WIS), Maohai Huang (CAS), Bing Zhang (UNLV) report on behalf
of a large collaboration:

European Space Agency's Herschel Space Observatory is scheduled to
make far infrared photometric observations of GRB 110422A on 30 April
around 14UT in 70�m and 170�m bands, and two follow-ups on 2-3 May
(time to be decided) in 70,170,250,350,500�m bands, and on 6-7 May in
250,350,500�m bands. This would be the first time a cosmological GRB
is observed in 70-350�m. Other facilities are encouraged to obtain
results of GRB 110422A across the spectrum on those Herschel observing
days.

GCN Circular 11976

Subject
GRB 110422A: Suzaku WAM observation of the prompt emission
Date
2011-04-26T11:08:37Z (14 years ago)
From
Masanori Ohno at ISAS/JAXA <ohno@astro.isas.jaxa.jp>
W. Iwakiri, Y. Terada, M. Tashiro,  K. Takahara, T. Yasuda (Saitama U.),
T. Uehara, Y. Hanabata, T. Takahashi, Y. Fukazawa (Hiroshima U.),
N. Vasquez (Tokyo Tech.) K. Yamaoka (Aoyama Gakuin U.),
M. Ohno, M. Kokubun, T. Takahashi (ISAS/JAXA),
S. Sugita (Nagoya U.), Y. E. Nakagawa (Waseda U.),
N. Ohmori, M. Akiyama, M. Yamauchi (Univ. of Miyazaki),
Y. Urata, P. Tsai (NCU), K. Nakazawa, K. Makishima (Univ. of Tokyo),
on behalf of the Suzaku WAM team, report:

The bright GRB 110422A (Swift/BAT trigger #451901 ; Mangano et al., GCN
11957; Palmer et al., GCN 11959) triggered the Suzaku Wide-band All-sky
Monitor (WAM) which covers an energy range of 50 keV - 5 MeV at 15:41:45
UT (=T0).

The observed light curve shows a multi-peaked structure starting at
T0-2s, ending at T0+35s with a duration (T90) of about 22 seconds. The
fluence in 100 - 1000 keV was 3.60 (+/- 0.14) x10-5 erg/cm2.
The 1-s peak flux measured from T0+18s was 14.5 (+/- 0.9) photons/cm2/s
in the same
energy range.

Preliminary result shows that the time-averaged spectrum from T0-2s to
T0+35s is well fitted by a single power-law with a photon index
of 2.83 (+/- 0.11) (chi2/d.o.f = 21.3/14).
All the quoted errors are at statistical 90% confidence level.


The light curves for this burst will be appeared at:
http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html

GCN Circular 11977

Subject
GRB 110422A: tentative redshift from TNG
Date
2011-04-26T15:51:06Z (14 years ago)
From
Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst <malesani@dark-cosmology.dk>
D. Malesani (DARK/NBI), D. Fugazza (INAF/Brera), P. D'Avanzo 
(INAF/Brera), V. D'Elia (ASI/ASDC), A. Melandri (INAF/Brera), S. 
Piranomonte (INAF/Roma), J.P.U. Fynbo (DARK/NBI), M. Cecconi (INAF/TNG), 
G. Mainella (INAF/TNG), report on behalf of a larger collaboration:

We observed the afterglow of GRB 110422A (Mangano et al., GCN 11957; 
Klunko et al., GCN 11958) with the Italian TNG located in La Palma. A 
single 700 s spectroscopic exposure could be taken due to rising 
humidity (see also Melandri et al., GCN 11963). Observations started on 
2011 April 22.998 UT (8.25 hr after the GRB). The adopted grism was 
LR-B, covering the wavelength range 3600-8200 AA.

We detect a clear absorption feature at 4290 AA. Interpreting this as 
the (unresolved) CIV doublet yields a redshift of z = 1.77. At the same 
redshift we find a few other lines which we interpret as due to Si IV 
and Fe II. We thus propose z = 1.77 to be the redshift of GRB 110422A.

GCN Circular 11978

Subject
GRB 110422A: Redshift confirmation from GTC
Date
2011-04-26T17:34:58Z (14 years ago)
From
Antonio Deugarte at IAA-CSIC <deugarte@iaa.es>
A. de Ugarte Postigo (DARK/NBI), A.J. Castro-Tirado, J. Gorosabel
(IAA-CSIC) report on behalf of a larger collaboration:

We have observed the afterglow of GRB 110422A  (Mangano et al., GCNC
11957; Klunko et al., GCNC 11958) using the 10.4m GTC telescope located in
La Palma (Spain). Spectroscopic observations were performed with mean
epoch of April 25th at 22:55 UT (3.3 days after the burst) and consisted
of a single 1800s exposure using the R500B grating (resolution ~500).

The spectrum shows several absorption features that we identify as due to
C IV, Al II, Al III, Fe II, Mg II, and Mg I at a redshift of
1.770+/-0.001, consistent with the results of Malesani et al. (GCNC
11977). We hence confirm this to be the redshift of the GRB.

We acknowledge excellent support from the GTC staff, in particular Rene
Ruten.

GCN Circular 11979

Subject
GRB 110422A: optical observations in CrAO, second epoch
Date
2011-04-26T20:25:41Z (14 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
V. Rumyantsev,  K. Antoniuk (CrAO), A. Pozanenko (IKI) report on behalf of 
larger GRB  follow-up collaboration:

We observed  the field of the Swift GRB 110422A (Mangano  et al., GCN 11957) 
with AZT-11 telescope of CrAO between  Apr. 24 (UT) 19:21 - 21:10. We detect 
the afterglow (Klunko et al. GCN 11958, Gres et al. GCN 11960, Xu et al. GCN 
11961). The photometry is based on the USNO B1.0 star 1651-0050626   (07 28 
13.15 +75 06 51.5) assuming R=18.56:

T0+      Filter,   Exposure, mag.
(mid, d)              (s)

2.1910   R        36x180       21.3 +/-0.3

GCN Circular 11985

Subject
GRB 110422A: Update of Herschel FIR observation schedule
Date
2011-04-29T17:15:41Z (14 years ago)
From
Maohai Huang at NAOC <mhuang@nao.cas.cn>
Maohai Huang (NAOC), Bing Zhang (UNLV), Dong Xu (WIS), Jinsong Deng
(NAOC), Liping Xin (NAOC), Yulei Qiu (NAOC) report on behalf of
Herschel OT1_mhuang01 Open Time program:

This is an update of ESA's schedule to search and observe far infrared
after glowof GRB 110422A using photometers of PACS (70,110micron) and
SPIRE (250, 350, 500micron) instruments on-board Herschel Space
Observatory, with sensitivities of several mJy/beam.

Date ----- Time ---- Instrument
2011-04-30T13:59:28UT PacsPhoto
2011-04-30T14:15:29UT PacsPhoto
2011-05-03T19:28:25UT SpirePhoto
2011-05-04T01:24:55UT PacsPhoto
2011-05-04T01:40:56UT PacsPhoto
2011-05-08T02:43:38UT SpirePhoto
2011-05-09T21:41:44UT PacsPhoto
2011-05-09T21:57:45UT PacsPhoto
2011-05-13T18:47:21UT SpirePhoto
For more details and updates (if any) see
http://herschel.esac.esa.int/observing/ScheduleReport.html

We strongly encourage ground and space instruments to collect data across
full spectral range, especially in X-ray, optical, near/mid IR,
millimeter/submillimeter, and radio bands, of GRB 110422A on observing
days of Herschel.

GCN Circular 11986

Subject
GRB 110422A: optical observations in CrAO
Date
2011-05-01T10:22:01Z (14 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
V. Rumyantsev (CrAO), A. Pozanenko (IKI), E. Klunko (ISTP) report on behalf 
of  larger GRB  follow-up collaboration:

We observed  the field of the Swift GRB 110422A (Mangano  et al., GCN 11957) 
with ZTSh telescope of CrAO on Apr. 28 between  (UT) 20:43: and  21:52. We 
clearly detect the afterglow (Klunko et al. GCN 11958, Gres et al. GCN 
11960, Xu et al. GCN 11961). The photometry is based on the USNO B1.0 star 
1651-0050626   (07 28 13.15 +75 06 51.5) assuming R=18.56 :

T0+      Filter,   Exposure, mag.
(mid, d)              (s)

6.2328  R        55x60       22.28  +/-0.14

GCN Circular 12006

Subject
GRB 110422A: Herschel FIR observation preliminary report
Date
2011-05-05T03:12:33Z (14 years ago)
From
Maohai Huang at NAOC <mhuang@nao.cas.cn>
Maohai Huang (NAOC), Bing Zhang (UNLV), Dong Xu (WIS), Jinsong Deng
(NAOC), Liping Xin (NAOC), Yulei Qiu (NAOC) report on behalf of Herschel
OT1_mhuang01 Open Time program:

Herschel Space Observatory has observed GRB 110422A according to the
plan (Huang et al GCN 11985).  Preliminary data reduction has shown
statistically significant (S/N ~ 10) detection in 170um and 250um bands
at a few mJy level. Scheduled follow-up observations and further
analyses of foreground/background sources will be conducted to
determine whether the emission is variable (dominated by the afterglow)
or from the host galaxy of GRB 110422A and Galactic ISM.

GCN Circular 12007

Subject
GRB 110422A: MASTER first 30 min OT light curve
Date
2011-05-05T06:42:02Z (14 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <gcncirc@observ.inetcomm.ru>
O. Gres, K.Ivanov, V.A.Poleshchuk, S.Yazev, N.M.Budnev, O.Chuvalaev
Irkutsk State University

V.Krushinski, I.Zalozhnich, A. Popov
Ural State University, Kourovka

E. Gorbovskoy, V. Lipunov, V.Kornilov, D.Kuvshinov, A.Belinski, N.Tyurina, 
N.Shatskiy, P.Balanutsa, V.V.Chazov, P.V.Kortunov, A.Kuznetsov, D.Zimnukhov, M. 
Kornilov, A.Kuznetsov, D.Zimnukhov, M. Kornilov, A.Sankovich
Sternberg Astronomical Institute, Moscow State University

A. Tlatov, A.V. Parhomenko, D. Dormidontov
Kislovodsk Solar Station of the Pulkovo Observatory

V.Yurkov, Yu.Sergienko, D.Varda, I.Kudelina
Blagoveschensk Educational State University, Blagoveschensk

  MASTER II  robotic telescope (MASTER-Net: http://observ.pereplet.ru)
located in Tunka (Baykal lake) was pointed to the  GRB 110422A (Mangano 
et al., GCN Circ 11957)  53 sec after GRB time at 2011-04-22 15:42:48.507 UT (Gres et al., GCN Circ 
11960). We see  OT (Klunko et al. GCN 11958) on all  images in both 
polarizations in R-band.

The results of the our photometry are:

  mag     err    exp      t-t_trig	 mag	 err	exp     t-t_trig
  R/              s        mean (hours)    R\	         s    mean (hours)
14.89	0.29	10	0.0166          15.28	0.43	10	0.0163
15.03	0.17	20	0.0272  	15.3	0.25	20	0.0272
16.04	0.47	30	0.0400          15.73	0.31	30	0.0397
15.73	0.38	40	0.0551   	15.77	0.38	40	0.0548
16.35	0.41	50	0.0729  	16.05	0.27	50	0.0724
16.53	0.37	60	0.0938  	16.53	0.32	60	0.0934
16.36	0.45	80	0.1190  	16.35	0.41	80	0.1186
16.68	0.34	100	0.1502  	16.78	0.33	100	0.1498
17.74	0.79	120	0.1871  	17.17	0.34	120	0.1868
17.78	0.59	150	0.2319	        17.52	0.33	150	0.2315
17.26	0.3	180	0.2834  	17.56	0.32	180	0.2831
17.22	0.33	180	0.3403  	17.78	0.48	180	0.3399
17.2	0.32	180	0.3957  	18.32	0.87	180	0.3952
17.59	0.45	180	0.4513  	18.71	1.27	180	0.4510
18.08	0.91	180	0.5066  	19.25	2.64	180	0.5063

The LC's are available at:
http://observ.pereplet.ru/images/GRB110422/grb110422.png

  The message may be cited.

Looking for U.S. government information and services? Visit USA.gov