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

GRB 150910A

GCN Circular 18264

Subject
GRB 150910A: Swift detection of a burst with an optical afterglow
Date
2015-09-10T09:26:53Z (10 years ago)
From
Kim Page at U.of Leicester <klp5@leicester.ac.uk>
C. Pagani (U Leicester), A. P. Beardmore (U Leicester),
A. A. Breeveld (UCL-MSSL), K. L. Page (U Leicester),
P. Romano (INAF-IASFPA) and T. N. Ukwatta (LANL) report on behalf of
the Swift Team:

At 09:04:48 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 150910A (trigger=655097). Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 5.675, +33.499 which is 
   RA(J2000) = 00h 22m 42s
   Dec(J2000) = +33d 29' 55"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty). As is typical for image triggers, the real-time
light curve does not show anything significant. 

The XRT began observing the field at 09:07:14.1 UT, 145.3 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 5.6669, 33.4717 which is equivalent to:
   RA(J2000)  = +00h 22m 40.06s
   Dec(J2000) = +33d 28' 18.1"
with an uncertainty of 5.1 arcseconds (radius, 90% containment). This
location is 101 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 153 seconds after the BAT trigger. There is a candidate afterglow in
the rapidly available 2.7'x2.7' sub-image at
  RA(J2000)  =	00:22:40.14 =	5.66723
  DEC(J2000) = +33:28:21.9  =  33.47275
with a 90%-confidence error radius of about 0.71 arc sec. This position is 3.9
arc sec. from the center of the XRT error circle. The estimated magnitude is
20.27 with a 1-sigma error of about  0.18. No correction has been made for the
expected extinction corresponding to E(B-V) of 0.05. 

Burst Advocate for this burst is C. Pagani (cp232 AT star.le.ac.uk). 
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 18265

Subject
GRB 150910A: KAIT Optical Afterglow Detection
Date
2015-09-10T10:00:52Z (10 years ago)
From
Weikang Zheng at UC Berkeley <weikang@berkeley.edu>
WeiKang Zheng and Alexei V. Filippenko (UC Berkeley) report on
behalf of the KAIT GRB team:

The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at
Lick Observatory, responded to Swift GRB 150910A (Pagani
et al., GCN 18264) starting at 09:34:20 UT, ~30 minutes after
the burst. Observations were performed with an automatic sequence
in the clear (roughly R), V, and I filters, and the exposure time was
20 s per image. The UVOT afterglow reported by Pagani et al. (GCN 18264)
was clearly detected in all filters. The brightness is about R~16.2 mag
at ~30 minutes after the burst, and is decreasing.
Follow-up observations are encouraged.

GCN Circular 18266

Subject
GRB 150910A: LCOGT FTN afterglow observations
Date
2015-09-10T11:05:14Z (10 years ago)
From
Cristiano Guidorzi at Ferrara U,Italy <guidorzi@fe.infn.it>
S. Dichiara, C. Guidorzi (U. Ferrara), S. Kobayashi (LJMU), A. Gomboc 
(U. Ljubljana), C. Mundell (U. Bath) on behalf of a larger collaboration 
report:

The 2-m LCOGT Faulkes Telescope North in Hawaii began observing Swift 
GRB 150910A (Pagani et al. GCN 18264) on September 10, 09:33:19 UT (28 
minutes after the burst trigger) with SDSS r and i filters. We clearly 
detect the optical afterglow (Pagani et al. GCN 18264; Zheng et al. GCN 
18265) with the following magnitudes:

Mid Time      Exposure       Filter       Magnitude
(min)           (s)
-------------------------------------------------------
29.0             60          r'           16.60 +- 0.02
35.6             60          i'           16.42 +- 0.02
-------------------------------------------------------

Calibration is done against SDSS magnitudes of nearby stars.

GCN Circular 18267

Subject
GRB 150910A: MITSuME Okayama Optical Observation
Date
2015-09-10T11:41:03Z (10 years ago)
From
Daisuke Kuroda at OAO/NAOJ <dikuroda@oao.nao.ac.jp>
D. Kuroda, K. Yanagisawa, Y. Shimizu, H. Toda (OAO, NAOJ),
S. Nagayama (NAOJ), M. Yoshida (Hiroshima), K. Ohta (Kyoto)
and N. Kawai(Tokyo Tech)
report on behalf of the MITSuME and OISTER collaboration:

We observed the field of GRB 150910A (Pagani et al., GCNC 18264)
with the optical three color (g', Rc and Ic) CCD camera attached
to the MITSuME 50cm telescope of Okayama Astrophysical Observatory.

The observation started on 2015-09-10 10:20:44 UT (~1.3 h after
the burst). We detected the previously reported afterglow (Pagani
et al., GCNC 18264; Zheng and Filippenko, GCNC 18265; Dichiara
et al., GCNC 18266) in all the three bands.

Photometric results of the OT are listed below.
We used SDSS-DR7 catalog for flux calibration.

#T0+[day]  MID-UT    T-EXP[sec]   g'  g'_err  Rc  Rc_err  Ic  Ic_err
-----------------------------------------------------------------------
0.05630    10:25:52     540.0     17.6 0.2    18.4 0.2    17.0 0.1
------------------------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]

GCN Circular 18268

Subject
GRB 150910A: Swift-BAT refined analysis
Date
2015-09-10T13:19:46Z (10 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@lheamail.gsfc.nasa.gov>
A. Y. Lien (GSFC/UMBC), S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC),
N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC),
C. Pagani (U Leicester), D. M. Palmer (LANL), T. Sakamoto (AGU),
M. Stamatikos (OSU), T. N. Ukwatta (LANL)
(i.e. the Swift-BAT team):
 
Using the data set from T-239 to T+963 sec from the recent telemetry downlinks,
we report further analysis of BAT GRB 150910A (trigger #655097)
(Pagani, et al., GCN Circ. 18264).  The BAT ground-calculated position is
RA, Dec = 5.677, 33.466 deg, which is 
   RA(J2000)  =  00h 22m 42.5s 
   Dec(J2000) = +33d 27' 56.8" 
with an uncertainty of 2.3 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 14%.
 
The mask-weighted light curve shows the burst definitely starting at ~T-150 sec
(and posibly before T-240 when we start having data), peaking at ~T+83 sec,
and ending at ~T+450 sec.  T90 (15-350 keV) is 112.2 +- 38.3 sec
(estimated error including systematics).
 
The time-averaged spectrum from T-5.00 to T+149.75 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.42 +- 0.12.  The fluence in the 15-150 keV band is 4.8 +- 0.4 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+82.89 sec in the 15-150 keV band
is 1.1 +- 0.4 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/655097/BA/

GCN Circular 18269

Subject
GRB 150910A: Nanshan optical observations
Date
2015-09-10T14:50:26Z (10 years ago)
From
Dong Xu at NAOC/CAS <dong.dark@gmail.com>
D. Xu (NAOC/CAS), Y. Qin (Geneva Observatory), Y.-D. Hu (IAA-CSIC),
Y.-H. Han (NAOC/CAS, HUST), X. Zhang, A. Esamdin, L. Ma (XAO) report:

We observed the field of GRB 150910A (Pagani et al., GCN 18264) using
the 1m telescope located at Nanshan, Xinjiang, China. We obtained
3x600s R-band frames with some floating clouds in the sky.

The afterglow (Pagani et al., GCN 18264; Zheng & Filippenko, GCN
18265) is detected in each of the frames. Preliminary results are as
follows

Mid Time  Exposure  Mag   MagErr
(hr)            (s)
4.91         600          19.40    0.20
5.14         600          19.55    0.20
5.31         600          19.30    0.20

and calibrated with the nearby SDSS field.

GCN Circular 18270

Subject
GRB 150910A: Swift/UVOT Detection of a Brightening Afterglow
Date
2015-09-10T16:11:49Z (10 years ago)
From
Marissa McCaule at PSU <marissamc@swift.psu.edu>
L. M. McCauley (PSU) and C. Pagani (U Leicester)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 150910A
154 s after the BAT trigger (Pagani et al., GCN Circ. 18264).
A source consistent with the XRT position
(Pagani et al. GCN Circ. 18264)
is detected in the initial UVOT exposures.

The preliminary UVOT position is:
    RA  (J2000) =  00:22:40.11 =   5.66713 (deg.)
    Dec (J2000) = +33:28:21.9  =  33.47274 (deg.)
with an estimated uncertainty of 0.58 arc sec. (radius, 90% confidence).

Preliminary detections using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) show a very rapid and steep
rise in the luminosity of the afterglow over the first 1 ks of observation.
Further investigation is strongly encouraged.
Preliminary detections for the early exposures are:


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

white                 153            303         147         19.90
white                 156            303         144         19.93
white                 592            612          19         17.09
white                 765            785          19         16.67
white                 866           1016         147         16.30
v                     135            145           9        >17.23
v                     642            662          19         16.64
v                     815            835          19         16.91
v                    1046           1066          19         16.11
b                     568            588          19         17.56
b                     741            761          19         16.87
u                     312            561         245         18.03
u                     312            561         245         18.02
u                     716            736          19         16.14
uvw1                  692            712          19         16.76
uvw2                 1022           1041          19        >17.97

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.05 in the direction of the burst
(Schlegel et al. 1998).

GCN Circular 18271

Subject
GRB 150910A: Enhanced Swift-XRT position
Date
2015-09-10T19:10:24Z (10 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.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 1428 s of XRT Photon Counting mode data and 5 UVOT
images for GRB 150910A, 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 = 5.66723, +33.47278 which is equivalent
to:

RA (J2000): 00h 22m 40.14s
Dec (J2000): +33d 28' 22.0"

with an uncertainty of 1.4 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 18272

Subject
GRB 150910A: Swift-XRT refined Analysis
Date
2015-09-10T22:26:03Z (10 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), A. Melandri
(INAF-OAB), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), D.N. Burrows
(PSU), T.G.R. Roegiers (PSU), L.M. McCauley (PSU) and C. Pagani report
on behalf of the Swift-XRT team:

We have analysed 8.0 ks of XRT data for GRB 150910A (Pagani et al. GCN
Circ. 18264), from 136 s to 35.1 ks after the  BAT trigger. The data
comprise 938 s in Windowed Timing (WT) mode (the first 7 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. 18271).

The late-time light curve (from T0+6.4 ks) can be modelled with a
series of power-law decays. The initial decay index is alpha=0.67
(+0.23, -0.21). At T+10.9 ks  the decay steepens to an alpha of 3.17
(+0.86, -0.30) before breaking again at T+20.3 ks to a final decay with
index alpha=1.3 (+/-0.4).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index	of 1.56 (+/-0.04). The
best-fitting absorption column is  1.30 (+0.16, -0.15) x 10^21 cm^-2,
in excess of the Galactic value of 5.4 x 10^20 cm^-2 (Willingale et al.
2013). The PC mode spectrum has a photon index of 1.77 (+0.09, -0.08)
and a best-fitting absorption column of 7.1 (+2.3, -1.7) x 10^20 cm^-2.
The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum  is 3.7 x 10^-11 (4.2 x 10^-11) erg cm^-2
count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:	     7.1 (+2.3, -1.7) x 10^20 cm^-2
Galactic foreground: 5.4 x 10^20 cm^-2
Excess significance: <1.6 sigma
Photon index:	     1.77 (+0.09, -0.08)

If the light curve continues to decay with a power-law decay index of
1.3, the count rate at T+24 hours will be 0.033 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.2 x
10^-12 (1.4 x 10^-12) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00655097.

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

GCN Circular 18273

Subject
GRB 150910A: Kast spectroscopy from 3m Shane telescope
Date
2015-09-11T00:05:09Z (10 years ago)
From
Weikang Zheng at UC Berkeley <weikang@berkeley.edu>
WeiKang Zheng, Alexei V. Filippenko and Heechan Yuk (UC Berkeley),
Yinan Zhu (NAOC) and Daniel A. Perley (Dark Cosmology Center)
report on behalf of the KAIT GRB team:

We observed the optical afterglow of GRB 150910A (Pagani et al., 
GCN 18264; Zheng & Filippenko, GCN 18265) with the Kast spectrograph
on the 3m Shane telescope at Lick Observatory, started at 10:08 UT
(about 1.1 hours after the burst), covering the 3500 - 10000 A   
wavelength range. A 1200-second and a 2400-second exposures
were acquired.

The spectrum shows blue continuum flux across the entire spectral
range. We detect absorption lines from Mg II (2796,2803) and Fe II
(2344,2374,2383) at a common redshift of z=1.359, as well as additional
lines further to the blue. We suggest this as the likely redshift of
the GRB.

GCN Circular 18274

Subject
GRB 150910A: Redshift from 10.4m GTC+OSIRIS
Date
2015-09-11T00:17:10Z (10 years ago)
From
Antonio de Ugarte Postigo at IAA-CSIC <deugarte@iaa.es>
Antonio de Ugarte Postigo (IAA-CSIC, DARK/NBI), Christina Thoene (IAA-CSIC), 
Gianluca Lombardi (IAC, ULL, GRANTECAN), and Alberto Perez (GRANTECAN) 
report on behalf of a larger collaboration:

We have observed the afterglow of GRB 150910A (Pagani et al., GCN 18264) 
using the 10.4 m GTC telescope equipped with OSIRIS. Our observation began 
at 23:11 UT (14.1 hr after the burst) and consisted of 3x900s exposures using the 
R1000B grism. The spectrum covers the wavelength range between 3700 and 
7800 AA.

The acquisition image shows the afterglow at a magnitude of r=20.65+/-0.07 as 
compared to SDSS stars.

The first spectrum shows a continuum throughout the full spectral range, with 
several absorption features that correspond to AlII, AlIII, FeII, MgII and MgI at a 
common redshift of 1.360, which we interpret as the redshift of the GRB.

GCN Circular 18275

Subject
GRB 150910A: SAO RAS optical photometry
Date
2015-09-11T02:06:57Z (10 years ago)
From
Moskvitin Alexander at SAO RAS <mosk@sao.ru>
A.S.Moskvitin (SAO RAS), V.P.Goranskij (SAI, Moscow State University),
report on behalf of larger GRB follow-up team:

We observed the field of the GRB 150910A (Pagani et al., GCN #18264)
with the Zeiss-1000, 1-meter telescope of SAO RAS (Russia),
equipped with the broadband filters UBVRcIc and EEV 42-40 CCD.
The observations started since 10.85 hours after the trigger.

We obtained sets of 6 x 300-sec. frames in Rc band three times per
September, 10/11 night. The OT (reported by Pagani et al., GCN #18264;
Zheng & Filippenko, GCN #18265; Dichiara et al., GCN #18266;
Kuroda et al., GCN #18267; Xu et al., GCN #18269; McCauley & Pagani,
GCN #18270; Zheng et al., GCN #18273; de Ugarte Postigo et al.,
GCN #18274) is clearly visible even in single frames.
The results of observations are as following.

#   (T_mid-T0),h   exp.,s     R_mag            time, UT
1.  11.035         6 x 300    20.20 +/- 0.05   19:56:03--20:17:48
2.  13.448         6 x 300    20.57 +/- 0.05   22:15:17--22:48:09
3.  15.739         6 x 300    20.78 +/- 0.05   00:32:30--01:05:46

Photometry is based on nearby SDSS stars (their magnitudes
were converted with the Lupon 2005 equations).

GCN Circular 18276

Subject
GRB 150910A: MITSuME Ishigakijima Optical Observation
Date
2015-09-11T04:46:31Z (10 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 and OISTER collaboration:

We observed the field of GRB 150910A (Pagani et al., GCNC 18264)
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 2015-09-10 12:21:44 UT (~3.3 h after
the burst). We detected the previously reported afterglow (Pagani
et al., GCNC 18264; Zheng and Filippenko, GCNC 18265; Dichiara
et al., GCNC 18266; Kuroda et al., GCNC 18267) in all the three
bands.

Photometric results of the OT are listed below.
We used GSC2.3 catalog for flux calibration.

#T0+[day]  MID-UT    T-EXP[sec]   g'  g'_err  Rc  Rc_err  Ic  Ic_err
-----------------------------------------------------------------------
0.14010    12:26:33     540.0     19.1 0.1    18.8 0.1    18.4 0.1
-----------------------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]

GCN Circular 18277

Subject
GRB 150910A: GROND observation of the afterglow
Date
2015-09-11T08:30:45Z (10 years ago)
From
Sebastian Schmidl at TLS Tautenburg <schmidl@tls-tautenburg.de>
S. Schmidl (TLS Tautenburg), F. Knust, and J. Greiner (both MPE Garching)
report on behalf of the GROND team:

We observed the field of GRB 150910A (SWIFT trigger 655097; Pagani et al,
GCN 18264) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008,
PASP 120, 405) mounted at the 2.2m MPG telescope at ESO La Silla
Observatory (Chile).

Observations started on September 11, 2015, at 05:08 UT, 20.1 hrs after the
GRB trigger. They were performed at an average seeing of 2.8" and at an
average airmass of 2.2.

We clearly detect the optical afterglow reported by Pagani et al. (GCN
18264), Zheng & Filippenko (GCN 18265), Dichiara et al. (GCN 18266),
Kuroda et al. (GCN 18267), Xu et al. (GCN 18269), de Ugarte Postigo et al.
(GCN 18274) and Moskvitin et al (GCN 18275).

Based on total exposures of 7.7 minutes in g'r'i'z'and 4.0 minutes in
JHK, at a midtime of 20.8 hrs after the burst, we measure the following
preliminary magnitudes (AB magnitude system):

g' = 21.5 +/- 0.2 mag,
r' = 21.2 +/- 0.2 mag,
i' = 21.0 +/- 0.2 mag,
z' = 20.8 +/- 0.2 mag,
J  > 19.8 mag,
H  > 19.3 mag, and
K  > 18.1 mag.

Given magnitudes and upper limits are calibrated against SDSS as well as
2MASS field stars and are not corrected for the expected Galactic
foreground extinction corresponding to a reddening of E_(B-V) = 0.05 mag
in the direction of the burst (Schlegel et al. 1998).

GCN Circular 18278

Subject
GRB 150910A: MITSuME Okayama Ks-band Observation
Date
2015-09-11T09:07:35Z (10 years ago)
From
Kenshi Yanagisawa at OAO/NAOJ <yanagi@oao.nao.ac.jp>
Kenshi Yanagisawa, Daisuke Kuroda, Yasuhiro Shimizu, Hideyuki
Izumiura (OAO/NAOJ), Michitoshi Yoshida (Hiroshima-U),
Kouji Ohta(Kyoto-U), and Nobuyuki Kawai(Tokyo Tech.) report
on behalf of the MITSuME collaboration:

We observed the field of GRB150910A (Pagani et al., GCNC 18264)
in Ks-band with a wide-field NIR camera at Okayama Astrophysical
Observatory (Japan). The camera has an effective aperture of 0.91m.

Observations started from 10:03 UT on 10th September, 59 min after
the BAT trigger, to 11:14 UT. The total exposure of 26 min was
successfully obtained.

In our co-add image, we found a single point source at
  R.A.(J2000) = 00:22:39.84
  DEC (J2000) = +33:28:20.5
with an uncertainty of of about 2 arcsec.

We estimate the magnitude Ks = 14.85 +/- 0.13 (Vega).
The calibration was made against 2MASS field stars.

T0+[min]    MID-UT     T-EXP[min]    Ks
------------------------------------------------------------
  +94       10:38        26          14.85 +/- 0.13 (Vega)
------------------------------------------------------------
T0+ : Elapsed time after the burst [min]
T-EXP: Total Exposure time [min]

GCN Circular 18279

Subject
GRB 150910A: NOT observations of the afterglow
Date
2015-09-11T13:06:31Z (10 years ago)
From
Zach Cano at U of Iceland <zewcano@gmail.com>
Z. Cano (U. Iceland), D. Malesani (DARK/NBI), A. de Ugarte Postigo
(IAA-CSIC, DARK/NBI), D. Xu (NAOC/CAS), J. Saario (NOT, U. Turku) and P.
Jakobsson (U. Iceland) report on behalf of a larger collaboration:

We observed the field of GRB 150910A (Pagani et al., GCN Circ. 18264) with
the 2.5-m Nordic Optical Telescope (NOT) equipped with MOSCA in two epochs
on the morning of 11-Sept-2015, at 01:10 and 04:45 UT, respectively.  In
SDSS filters r (epoch 1) and ugrz (epoch 2) we clearly detect the optical
afterglow (e.g. Zheng & Filippenko, GCN Circ. 18265).

A summary of our photometry is as follows:

-------------------------------------------------------
filter (SDSS)        t-t0 (hr)            mag +- merr
-------------------------------------------------------
   r                  16.27              20.85 +- 0.18
   r                  20.18              21.24 +- 0.21
   u                  20.05              21.82 +- 0.24
   g                  20.24              21.49 +- 0.22
   z                  19.84              20.78 +- 0.24

These magnitudes are calibrated to SDSS and are not corrected for
foreground extinction.  We note that these magnitudes are in good agreement
with those obtained by GROND (Schmidl et al., GCN Circ. 18277) at a
contemporaneous post-explosion epoch.  Compared with other datasets, e.g.
Xu et al. (GCN Circ. 18269), our second epoch of r-band observations
implies a power-law like decay in time, e.g. f(t)=t^-alpha, with a decay
slope of alpha=1.
���1.

GCN Circular 18281

Subject
GRB 150910A: TSHAO optical observations
Date
2015-09-11T19:27:21Z (10 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
E. Mazaeva (IKI), I. Reva (Fesenkov Astrophysical Institute),   A. 
Kusakin (Fesenkov Astrophysical Institute), A. Volnova (IKI), A. 
Pozanenko  (IKI) report on behalf of larger GRB follow-up collaboration:

We observed the field of GRB 150910A (Pagani et al., GCN  18264)  with 
Zeiss-1000 (East) 1-m telescope of Tien Shan Astronomical Observatory on 
Sep. 10 (UT) 18:02:59 -- 20:37:38.  We obtained several images in R and 
B filters.  In both filters the afterglow  (Pagani et al., GCN 18264; 
Zheng & Filippenko, GCN 18265) is clearly visible. Within 2.5 hours of 
observations we do not detect significant fading of the afterglow. The 
photometry of combined images are following

Date       UT start    t-T0     Filter  Exp.     OT       Err
                        (mid, days)      (s)

2015-09-10 18:08:20    0.42807  R       11*300   20.18 +/- 0.05
2015-09-10 18:02:59    0.42436  B       12*300   20.85 +/- 0.08

The photometry is based on nearby SDSS stars

SDSS_id            R(Lupton)
J002232.47+332751.3    16.29
J002236.24+332854.2    15.92
J002241.61+332836.1    16.23
J002248.33+332723.4    16.76
J002231.90+333004.8    16.93
J002225.39+332809.6    16.12
J002246.76+332716.9    17.63

Our photometry in R-filter is in agreement with  in subsequent 
observations (Moskvitin & Goranskij, GCN 18275).

GCN Circular 18284

Subject
GRB 150910A: continued SAO RAS optical observations
Date
2015-09-11T22:20:23Z (10 years ago)
From
Moskvitin Alexander at SAO RAS <mosk@sao.ru>
A. S. Moskvitin (SAO RAS), report on behalf of larger GRB follow-up team:

The field of the GRB 150910A (Pagani et al., GCN #18264) was observed
with the Zeiss-1000 telescope of SAO RAS (Russia) in Rc band
on September, 11.791 (T_mid-T0 = 1.413 days), 17:55:54--20:01:44 UT.

20 x 300 seconds frames were obtained. The OT is still clearly visible
in the stacked image. The brightness of the object R = 22.2 +/- 0.10
(based on the same SDSS stars as in previous circular GCN #18275).

GCN Circular 18285

Subject
GRB 150910A: VLA Detection
Date
2015-09-11T22:54:59Z (10 years ago)
From
Kate Alexander at Harvard <kalexander@cfa.harvard.edu>
K. Alexander (Harvard), T. Laskar (NRAO / UC Berkeley), and E. Berger
(Harvard) report on behalf of a larger collaboration:

We observed GRB 150910A (Pagani et al; GCN 18264) at multiple frequencies
with the Karl G. Jansky Very Large Array (VLA) beginning 2015 September
11.10 UT (0.72 days after the burst). At a mean frequency of 9.8 GHz, we
detect a radio source with a preliminary flux density of ~ 0.1 mJy at

RA = 00:22:40.120 +/- 0.021
Dec = +33:28:21.750 +/- 0.036

consistent with the UVOT optical position (McCauley et al; GCN 18270) and
the enhanced Swift/XRT position (Evans et al.; GCN 18271). Follow-up
observations are planned.

GCN Circular 18287

Subject
GRB 150910A: Chuguev observatory optical observations
Date
2015-09-12T02:51:11Z (10 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
Yu. Krugly (IA KhNU),  E. Mazaeva (IKI), V. Shevchenko  (IA KhNU),  T. 
Gromakina (IA KhNU), I. Molotov (KIAM), A. Pozanenko  (IKI) report on 
behalf of larger GRB follow-up collaboration:

We observed the field of GRB 150910A (Pagani et al., GCN  18264)  with 
0.7m  telescope of Institute of Astronomy, Kharkiv National University 
starting on Sep. 10 (UT) 21:41:15. We obtained several images in R B 
filter.   The afterglow  (Pagani et al., GCN 18264; Zheng & Filippenko, 
GCN 18265) is clearly visible in a combined image. The photometry of the 
combined image is following

Date       UT start    t-T0     Filter  Exp.     OT       Err
                        (mid, days)      (s)

2015-09-10 21:41:15    0.52235  R       11*180   20.25 +/-0.14

The photometry is based on SDSS stars used in GCN 18281 (Mazaeva et al.)

GCN Circular 18288

Subject
GRB 150910A: MITSuME Ishigakijima Optical Observation after 1 day
Date
2015-09-12T02:51:13Z (10 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 and OISTER collaboration:

We observed the field of GRB 150910A (Pagani et al., GCNC 18264)
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 2015-09-11 12:29:42 UT (~1.14 days after
the burst). We detected the previously reported afterglow (Pagani
et al., GCNC 18264; Zheng and Filippenko, GCNC 18265; Dichiara
et al., GCNC 18266; Kuroda et al., GCNC 18267) in g' and Rc bands.

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

#T0+[day]  MID-UT    T-EXP[sec]   g'  g'_err  Rc  Rc_err  Ic  Ic_err                                                                    
-----------------------------------------------------------------------
1.21526    14:14:46    4800.0     21.8 0.2    21.2 0.2    >20.8
-----------------------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]

GCN Circular 18289

Subject
GRB 150910A: AAO optical observations
Date
2015-09-12T03:14:23Z (10 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
E. Mazaeva (IKI), R. Inasaridze (AAO), V. Zhuzhunadze (AAO), I. Molotov 
(KIAM), A. Pozanenko (IKI) report on behalf of larger GRB follow-up 
collaboration:

We observed the field of GRB 150910A (Pagani et al., GCN  18264)  with 
  with AS-32 (0.7m) telescope of Abastumani Observatory starting on Sep. 
10 (UT) 18:53:54. We obtained several unfiltered images. The afterglow 
(Pagani et al., GCN 18264; Zheng & Filippenko, GCN 18265) is clearly 
visible in a combined image. The photometry of the combined image is 
following

Date       UT start    t-T0     Filter  Exp.     OT       Err
                        (mid, days)      (s)

2015-09-10 18:53:54    0.45834  none    50*120   20.16 +/- 0.06

The photometry is based on SDSS stars used in GCN 18281 (Mazaeva et al.)

GCN Circular 18295

Subject
GRB150910A: P60 Observations
Date
2015-09-12T16:15:10Z (10 years ago)
From
Daniel Perley at Caltech <dperley@astro.caltech.edu>
D. A. Perley (DARK) and S. B. Cenko (NASA/GSFC) report:

We observed the location of GRB 150910A (Pagani et al., GCN 18264) using 
the robotic Palomar 60-inch telescope on two epochs during the night of 
2015-09-11 UT, and an additional epoch during the night of 2015-09-12 
UT.  During each epoch we acquired 3x180s of imaging in each of the g', 
r', and i' filters.

The optical afterglow (Pagani et al.; Zheng and Filippenko, GCN 18265) 
is detected in each observation.  Preliminary photometry relative to 
SDSS yields:

t_start(d)  filt   mag      emag
    0.973    i  =  21.24 +/- 0.12
    0.980    g  =  21.54 +/- 0.06
    0.989    r  =  21.35 +/- 0.08
    1.067    i  =  21.28 +/- 0.07
    1.074    g  =  21.85 +/- 0.06
    1.081    r  =  21.50 +/- 0.06
    2.060    i  =  22.21 +/- 0.17
    2.067    g  =  22.66 +/- 0.14
    2.074    r  =  23.03 +/- 0.26

GCN Circular 18301

Subject
GRB 150910A: MITSuME Ishigakijima Optical Observation after 2 days
Date
2015-09-13T00:03:14Z (10 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 and OISTER collaboration:

We observed the field of GRB 150910A (Pagani et al., GCNC 18264)
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 2015-09-12 13:59:26 UT (~2.2 days after
the burst). We detected the previously reported afterglow (Pagani
et al., GCNC 18264; Zheng and Filippenko, GCNC 18265; Dichiara
et al., GCNC 18266; Kuroda et al., GCNC 18267) in Rc band.

Photometric results and three sigma upper limit 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
-----------------------------------------------------------------------
2.22658    14:31:04    3240.0    >22.4   22.3 0.4   >20.73
-----------------------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]

GCN Circular 18302

Subject
GRB 150910A: RATIR Observations
Date
2015-09-13T16:22:24Z (10 years ago)
Edited On
2024-11-07T19:44:37Z (7 months ago)
From
Nat Butler at UC berkeley <natxbutler@gmail.com>
Edited By
Vidushi Sharma at NASA GSFC/UMBC <vidushi.sharma@nasa.gov> on behalf of Leo P. Singer at NASA/GSFC <leo.p.singer@nasa.gov>
Nat Butler (ASU), Alan M. Watson (UNAM), Alexander Kutyrev (GSFC), William H. Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (UCB), J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (GSFC/STScI), Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), José A. de Diego (UNAM), Leonid Georgiev (UNAM), Jesús González (UNAM), Carlos Román-Zúñiga (UNAM), Neil Gehrels (GSFC), Harvey Moseley (GSFC), John Capone (UMD), V. Zach Golkhou (ASU), and Vicki Toy (UMD) report:

We observed the field of GRB 150910A (Pagani et al., GCN 18264) with the Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the 1.5m Harold Johnson Telescope at the Observatorio Astronómico Nacional on Sierra San Pedro Mártir from 2015/09 13.15 to 2015/09 13.26 UTC (66.44 to 69.21 hours after the BAT trigger), obtaining a total of 0.99 hours exposure in the r, i, and z bands.

The optical afterglow (Pagani et al.; Zheng and Filippenko, GCN 18265) is well detected.  In comparison with the SDSS DR9 catalog, we obtain:

   r 22.44 +/- 0.13
   i 22.31 +/- 0.11
   z > 20.29 (3-sigma)

These magnitudes are in the AB system and are not corrected for Galactic extinction in the direction of the GRB.

We thank the staff of the Observatorio Astronómico Nacional in San Pedro Mártir.

GCN Circular 18306

Subject
GRB 150910A: Mt. Terskol observatory optical observation
Date
2015-09-14T07:16:41Z (10 years ago)
From
Alexei Pozanenko at IKI <alex@grb.rssi.ru>
M. Andreev (Terskol Branch of INASAN), E. Mazaeva (IKI), A. Sergeev (Terskol Branch of INASAN), A. Volnova (IKI), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration:

We observed the field of GRB 150910A (Pagani et al., GCN 18264) with Zeiss-600 telescope of Mt. Terskol observatory in R-filter starting on Sep. 10 (UT) 20:45:05. We obtained several unfiltered images. The afterglow (Pagani et al., GCN 18264; Zheng & Filippenko, GCN 18265) is clearly detected in a combined image. The photometry of the combined image is following

Date UT start t-T0 Filter Exp. OT Err
(mid, days) (s)

2015-09-10 20:45:05 0.51974 R 46*120 20.46 +/- 0.07

The photometry is based on SDSS stars used in GCN 18281 (Mazaeva et al.)

GCN Circular 18312

Subject
GRB 150910A: Continued RATIR Observations
Date
2015-09-14T17:25:20Z (10 years ago)
Edited On
2024-11-07T19:33:43Z (7 months ago)
From
Nat Butler at UC berkeley <natxbutler@gmail.com>
Edited By
Vidushi Sharma at NASA GSFC/UMBC <vidushi.sharma@nasa.gov> on behalf of Leo P. Singer at NASA/GSFC <leo.p.singer@nasa.gov>
Nat Butler (ASU), Alan M. Watson (UNAM), Alexander Kutyrev (GSFC), William H. Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (UCB), J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (GSFC/STScI), Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), José A. de Diego (UNAM), Leonid Georgiev (UNAM), Jesús González (UNAM), Carlos Román-Zúñiga (UNAM), Neil Gehrels (GSFC), Harvey Moseley (GSFC), John Capone (UMD), V. Zach Golkhou (ASU), and Vicki Toy (UMD) report:

We observed the field of GRB 150910A (Pagani et al., GCN 18264) with the Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the 1.5m Harold Johnson Telescope at the Observatorio Astronómico Nacional on Sierra San Pedro Mártir from 2015/09 14.17 to 2015/09 14.46 UTC (90.88 to 98.01 hours after the BAT trigger), obtaining a total of 1.71 hours exposure in the r, i, and z bands.

The optical afterglow (Pagani et al.; Zheng and Filippenko, GCN 18265) is well detected.  In comparison with the SDSS DR9 catalog, we obtain:

   r = 22.23 +/- 0.09
   i = 22.44 +/- 0.10
   z > 19.89 (3-sigma)

These magnitudes are in the AB system and are not corrected for Galactic extinction in the direction of the GRB.  Compared to our previous night of observations (Butler et al., GCN 18302), the source flux is consistent with remaining constant at the ~1-sigma level.  Also, the source appears to be extended in our images, suggesting that the flux may be dominated by the GRB host galaxy.

We thank the staff of the Observatorio Astronómico Nacional in San Pedro 
Mártir.

GCN Circular 18314

Subject
GRB 150910A: T100 observations
Date
2015-09-15T08:24:52Z (10 years ago)
From
Eda Sonbas at NASA/GSFC <edasonbas@gmail.com>
E. Sonbas (Adiyaman Univ.), O. Basturk (Ankara Univ.), T. Guver (Istanbul
Univ.), E. Gogus (Sabanci Univ.), S. Eryilmaz, O. Erece, H. Kirbiyik (TUG)
report on behalf of a larger collaboration


We observed the field of Swift GRB 150910A (Pagani et al., GCN#18264) with
the 1.0 meter T100 telescope (Bakirlitepe, TUBITAK National Observatory,
Turkey), starting September, 10, 20:08:16 UT (~ 11 hours after the
trigger). Observations were carried out in the R filter. The afterglow is
detected in the R band images with an exposure time of 300 s.


Using USNO-B1 star USNO-B1 1234-0008068 (R.A.=5.65, Dec=+33.45) in the
field, the magnitudes of the OT were estimated as follows;


t-t0 (hr) exp.(s) filt mag err (+/-)

10.97 300 R 20.09 0.23

11.06 300 R 20.18 0.25


Analysis of further observations with the same filter is ongoing.


We thank to TUBITAK National Observatory for a partial support in using
T100 telescope with project number 10CT100-95 and technical support.

GCN Circular 18319

Subject
GRB 150910A: TSHAO optical observations
Date
2015-09-16T11:35:17Z (10 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
A. Volnova (IKI), I. Reva (Fesenkov Astrophysical Institute), A. Kusakin 
(Fesenkov Astrophysical Institute), E. Mazaeva (IKI),  A. Pozanenko 
(IKI) report on behalf of larger GRB follow-up collaboration:

We observed the field of GRB 150910A (Pagani et al., GCN  18264)  with 
Zeiss-1000 (East) 1-m telescope of Tien Shan Astronomical Observatory on 
Sep. 11 and Sep. 12.  We obtained several images in R filter.  The 
afterglow  (Pagani et al., GCN 18264; Zheng & Filippenko, GCN 18265) is 
clearly visible in a combined image on Sep. 11 and on Sep. 12 we 
obtained upper limit.  The photometry of the combined images are following

Date       UT start    t-T0     Filter  Exp.     OT       Err
                        (mid, days)      (s)

2015-09-11 18:39:41    1.38753  R       16*300   21.87    0.10
2015-09-12 19:03:44    2.39553  R       21*300   >22.3   (3 sigma)

The photometry is based on SDSS stars used in GCN 18281 (Mazaeva et al.)

GCN Circular 18320

Subject
GRB 150910A: Mt. Terskol observatory optical observations
Date
2015-09-16T11:45:10Z (10 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
A. Volnova (IKI), A. Sergeev (Terskol Branch of INASAN), M. Andreev 
(Terskol Branch of INASAN),  E. Mazaeva (IKI), A. Pozanenko (IKI) report 
on behalf of larger GRB follow-up collaboration:

We observed the field of GRB 150910A (Pagani et al., GCN 18264) with 
Zeiss-2000 telescope of Mt. Terskol observatory in R-filter starting on 
Sep. 11 (UT) 00:40:58.  The afterglow (Pagani et al., GCN 18264; Zheng & 
Filippenko, GCN 18265) is clearly detected in a each image. The 
photometry of a combined image is following

Date UT start       t-T0    Filter Exp.   OT     Err
                     (mid, days)    (s)

2015-09-11 00:40:58 0.67083 R      13*120 20.90  0.07

The photometry is based on SDSS stars used in GCN 18281 (Mazaeva et al.)

GCN Circular 18327

Subject
GRB 150910A: AAO optical observations
Date
2015-09-17T07:27:12Z (10 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
E. Mazaeva (IKI), R. Inasaridze (AAO), O. Kvaratskhelia(AAO), I. Molotov 
(KIAM), A. Pozanenko (IKI) report on behalf of larger GRB follow-up 
collaboration:

We observed the field of GRB 150910A (Pagani et al., GCN  18264)  with 
AS-32 (0.7m) telescope of Abastumani Observatory starting on Sep. 11 
(UT) 20:32:45. We obtained several unfiltered images. The afterglow 
(Pagani et al., GCN 18264; Zheng & Filippenko, GCN 18265) is clearly 
visible in a combined image. The photometry of the combined image is 
following

Date       UT start    t-T0     Filter  Exp.     OT       Err
                        (mid, days)      (s)

2015-09-11 20:32:45    1.46327  none    49*120   21.55 +/- 0.08

The photometry is based on SDSS stars used in GCN 18281 (Mazaeva et 
al.), R magnitude deduced from Lupton's transformations.

GCN Circular 18556

Subject
GRB 150910A: CrAO optical observations
Date
2015-11-03T19:13:53Z (10 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
V. Rumyantsev (CrAO), E. Mazaeva (IKI),  A. Volnova (IKI), A. Pozanenko
(IKI) report on  behalf of larger GRB follow-up collaboration:

We observed the field of the Swift GRB 150910A (Pagani et al., GCN
18264) with ZTSh telescope of CrAO observatory on Sep. 11 and Sep. 12.
We took several images in R,B-filters of 120 s exposure under good
weather conditions on Sep. 11 and non-optimal weather conditions (mean
seeing of 4") on Sep. 12.

The photometry of the afterglow (Pagani et al., GCN 18264; Zheng &
Filippenko, GCN 18265) is following

Date       UT start,  t-t0     Filter   Exp.    OT    OT_err UL(3sigma)
                       (mid, days)        (s)

2015-09-11 17:56:37   1.3762   R        10*120  21.69 0.12   22.9
2015-09-11 18:18:31   1.4022   B        20*120  22.48 0.15   23.5
2015-09-11 18:39:47   1.4244   R        10*120  21.82 0.10   23.2
2015-09-11 19:22:17   1.4436   B        16*120  22.09 0.10   23.5
2015-09-12 18:04:32   2.3801   R        10*120  n/d   n/a    22.3

The photometry is based on SDSS stars used in GCN 18281 (Mazaeva et al.)

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