GRB090323A

This page lists all entries on GRB090323A in GRBweb

Summary Fermi GBM IPN Fermi LAT GCN 9021 GCN 9023 GCN 9024 GCN 9026 GCN 9027 GCN 9028 GCN 9030 GCN 9031 GCN 9032 GCN 9033 GCN 9034 GCN 9035 GCN 9036 GCN 9037 GCN 9039 GCN 9041 GCN 9042 GCN 9043 GCN 9047 GCN 9051 GCN 9063 GCN 9324

Summary table
Variable Value Source
GRB_name_Fermi GRB090323002
T0 0:02:42 UTC Fermi_LAT
ra 190.7096° Fermi_LAT
decl 17.0533° Fermi_LAT
pos_error 1.39e-05° Fermi_LAT
T90 133.89 s Fermi_GBM
T90_error 0.572 s Fermi_GBM
T90_start 0:02:51.331 UTC Fermi_GBM
fluence 1.08e-04 erg/cm² Fermi_GBM
fluence_error 4.16e-08 erg/cm² Fermi_GBM
redshift 3.5700
T100 143.221 s
GBM_located False
mjd 54913.001875 Fermi_LAT
Fermi GBM table
GRB_name_Fermi GRB090323002
trigger_name bn090323002
ra 190.7000°
decl 17.1000°
pos_error 2.80e+00°
datum 2009-03-23
t_trigger 0:02:42.627 UTC
T90 133.89 s
T90_error 0.572 s
T90_start 0:02:51.331 UTC
fluence 1.08e-04 erg/cm²
fluence_error 4.16e-08 erg/cm²
flux_1024 1.34e+01 erg/cm²/s
flux_1024_error 3.01e-01 erg/cm²/s
flux_1024_time 1.41e+02 erg/cm²/s
flux_64 1.63e+01 erg/cm²/s
flux_64_error 1.23e+00 erg/cm²/s
IPN table
GRB_name GRB090323A
ra 190.6917°
decl 17.0833°
pos_error 1.33e-01°
redshift 3.5700
Fermi LAT table
GRB_name_Fermi GRB090323002
GRB_name GRB090323A
MET 259459364.0
datum 2009-03-23
t_trigger 0:02:42 UTC
ra 190.7096°
decl 17.0533°
pos_error 1.39e-05°
GCN 9021 table
GRB_name GRB090323A
GCN_number 9021
Detection_method Fermi GBM Other
ra 190.6900°
decl 17.0800°
Circular_text TITLE: GCN CIRCULAR NUMBER: 9021 SUBJECT: Fermi GBM and LAT detections of GRB 090323 DATE: 09/03/23 21:24:41 GMT FROM: Alexander van der Horst at NASA/MSFC Masanori Ohno (ISAS/JAXA), Sara Cutini (ASDC), Julie McEnery (NASA/GSFC), Jim Chiang (SLAC/KIPAC), Elmar Koerding (AIM/Saclay) report on behalf of the Fermi LAT team, and Alexander van der Horst (NASA/MSFC/ORAU) reports on behalf of the Fermi GBM team. "At 00:02:42.63 UT on 23 March 2009, the Fermi Gamma-Ray Burst Monitor (GBM) triggered and located GRB 090323 (trigger 259459364 / 090323002). The GBM light curve consists of multiple peaks and has a duration of ~150 seconds. The Fermi Large Area Telescope (LAT) has significantly, with more than 5 sigma, detected this GRB. Emission was observed in the LAT up to a few GeV. The high-energy emission commences several seconds after the GBM trigger time, and we see marginal evidence in the LAT that it continues for up to a couple of kilo-seconds. The best LAT on-ground localization is found to be (RA,Dec=190.69, 17.08) with a 68% (resp. 90%) containment radius of 0.09 deg (resp. 0.14, statistical), and a systematic error less than 0.1 deg. The GBM on-ground localization is consistent with this LAT localization within statistical and systematic uncertainties. We further report that the Fermi Observatory executed a maneuver following this trigger and tracked the burst location for the next 5 hours, subject to Earth-angle constraints. Further analysis is ongoing. The points of contact for this burst are Masanori Ohno (LAT, ohno@astro.isas.jaxa.jp) and Alexander van der Horst (GBM, Alexander.J.VanDerHorst@nasa.gov). The Fermi LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden. This message can be cited."
GCN 9023 table
GRB_name GRB090323A
GCN_number 9023
Detection_method IPN Triangulation
ra 149.9800°
decl 11.2320°
Circular_text TITLE: GCN CIRCULAR NUMBER: 9023 SUBJECT: IPN triangulation of GRB090323 DATE: 09/03/23 23:21:41 GMT FROM: Kevin Hurley at UCBerkeley/SSL K. Hurley and J. Goldsten, on behalf of the MESSENGER NS GRB team, A. von Kienlin, G. Lichti, and A. Rau, on behalf of the INTEGRAL SPI-ACS GRB team, and V. Connaughton, M. Briggs, and C. Meegan, on behalf of the Fermi GBM team, report: MESSENGER (GRNS) and INTEGRAL (SPI-ACS) have so far observed GRB090323 (Ohno et al. GCN 9021). We have triangulated this burst to a preliminary annulus centered at RA, Dec = 149.980, +11.232, whose radius is 39.826 +/- 0.286 degrees (3 sigma). This annulus intersects the GBM localization, and the LAT localization lies 0.007 degrees from the center line of this annulus. A map has been posted at ssl.berkeley.edu/ipn3/090323 showing the GBM contours and best-fit position, the IPN annulus, and the LAT best-fit position and error circle. The IPN localization may be improved.
GCN 9024 table
GRB_name GRB090323A
GCN_number 9024
Detection_method Swift-XRT Other
ra 190.7094°
decl 17.0539°
Circular_text TITLE: GCN CIRCULAR NUMBER: 9024 SUBJECT: GRB 090323: Possible XRT Counterpart DATE: 09/03/24 03:31:40 GMT FROM: Jamie A. Kennea at PSU/Swift-XRT J. Kennea (PSU), P. Evans and M. Goad (U Leicester) report on behalf of the Swift/XRT Team: At 19:27UT on March 23rd, 2009, Swift began a TOO observation of the Fermi/LAT error circle of GRB 090323 (GCN #9021). Ground analysis of the initial data finds an uncatalogued point source inside the LAT error circle. Currently only one orbit of data has been downlinked so it is not possible to determine if the source is fading. Using 1137 s of XRT Photon Counting mode data and 2 UVOT images, 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 = 190.70940, 17.05390 which is equivalent to: RA (J2000): 12 42 50.26 Dec (J2000): +17 03 14.2 with an uncertainty of 2.7 arcsec (radius, 90% confidence). This position is 1.9 arcminutes from the LAT on-ground localization given in GCN #9021. 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 http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an extension of this method.
GCN 9026 table
GRB_name GRB090323A
GCN_number 9026
Detection_method GROND
ra 190.7095°
decl 17.0532°
redshift 4.0000
Circular_text TITLE: GCN CIRCULAR NUMBER: 9026 SUBJECT: GRB 090323: GROND Detection of the Afterglow and Photo-z DATE: 09/03/24 05:06:41 GMT FROM: Adria C. Updike at Clemson U Adria C. Updike (Clemson University), Robert Filgas (Tautenburg Obs.), Thomas Kruehler, Jochen Greiner (MPE Garching), and Sheila McBreen (University College Dublin) report on behalf of the GROND team: We observed the field of GRB 090323 (Fermi trigger 259459364 / 090323002; Ohno et al., GCN #9021) 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). Observations started at 02:50 UT on March 24, 26 hours and 48 minutes time after the GRB trigger, and are continuing. They were performed at an average seeing of 1.3" and at an average airmass of 1.8. We found a single point source within the 2.7" Swift-XRT error circle reported by Kennea et al. (GCN #9024) at RA (J2000) = 12h 42m 50.29s DEC (J2000) = +17d 03' 11.6" with an uncertainty of 0.5". Based on the first 8 min of total exposures in g'r'i'z' J H Ks, we estimate preliminary magnitudes (all in AB system) of g' = 21.64 +/- 0.07 mag, r' = 20.03 +/- 0.03 mag, i' = 19.64 +/- 0.02 mag, z' = 19.39 +/- 0.02 mag, J = 19.24 +/- 0.02 mag, H = 18.86 +/- 0.02 mag, and K = 18.58 +/- 0.03 mag Given magnitudes are calibrated against GROND zeropoints as well as 2MASS field stars and are not corrected for the expected Galactic foreground extinction corresponding to a reddening of E_(B-V)= 0.02 mag in the direction of the burst (Schlegel et al. 1998). Based on the given magnitudes, we find a photometric redshift of z = 4.0 +/- 0.3.
GCN 9027 table
GRB_name GRB090323A
GCN_number 9027
Detection_method Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 9027 SUBJECT: GRB 090323: P60 Afterglow Confirmation DATE: 09/03/24 05:55:03 GMT FROM: S. Bradley Cenko at Caltech S. B. Cenko and D. A. Perley (UC Berkeley) report on behalf of a larger collaboration: We have imaged the field of GRB090323 (Ohno et al., GCN 9021) with the automated Palomar 60-inch telescope. Observations were taken in the Sloan r' and i' filters beginning at 2009 Mar 24 04:20 UT (~ 28.30 hr after the burst). Inside the XRT error circle (Kennea et al., GCN 9024) we find a single source consistent with the position repored by Updike et al (GCN 9026). At this epoch we measure magnitudes of r' = 20.5, i' = 20.0, suggesting the source has faded since the observations reported therein (referenced with respected to several nearby SDSS sources). We therefore confirm this object is the afterglow of GRB090323.
GCN 9028 table
GRB_name GRB090323A
GCN_number 9028
Detection_method Other
redshift 3.5700
Circular_text TITLE: GCN CIRCULAR NUMBER: 9028 SUBJECT: GRB 090323 Gemini-South Redshift DATE: 09/03/24 07:18:48 GMT FROM: Ryan Chornock at UC Berkeley R. Chornock, D. A. Perley, S. B. Cenko, and J. S. Bloom (UC Berkeley) report on behalf of a larger collaboration: We performed spectroscopy on the afterglow of GRB 090323 (Ohno et al., GCN 9021; Updike et al., GCN 9026; Cenko and Perley, GCN 9027) using Gemini-South (GMOS) starting at 05:58 UT on 2009-03-24, approximately 30 hours after the trigger. We conducted a series of four exposures of 600 seconds, two using the B600 grating centered at 6000 Angstroms and two with the R400 grating centered at 8000 Angstroms. The first spectrum shows strong absorption blueward of 5580 Angs, which we identify as the onset of the Lyman-alpha forest at z=3.6. There are also narrow absorptions with multiple components from C IV, O I, C II, and Si IV at a consistent redshift of z=3.57. Further analysis is ongoing. We would like to thank the Gemini-S staff, in particular Etienne Artigau, Lucas Fuhrman, and Benoit Neichel, for their support with these observations.
GCN 9030 table
GRB_name GRB090323A
GCN_number 9030
Detection_method Konus-Wind Det
t_trigger 0:02:54.632 UTC
Circular_text TITLE: GCN CIRCULAR NUMBER: 9030 SUBJECT: Konus-Wind observation of GRB 090323 DATE: 09/03/24 12:25:07 GMT FROM: Valentin Pal'shin at Ioffe Inst 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 GRB 090323 (Fermi-GBM trigger 259459364 / 090323002) localized by Fermi-LAT (Ohno et al., GCN 9021; the LAT localization was confirmed by the IPN triangulation: Hurley et al., GCN 9023) triggered Konus-Wind at T0=174.632 s UT (00:02:54.632). The burst light curve shows several pulses with a total duration of ~160 s, followed by a weak tail marginally seen up to ~T0+300 s in all energy bands. As observed by Konus-Wind the burst had a fluence of 2.02(-0.25, +0.28)x10^-4 erg/cm2, and a 256-ms peak flux measured from T0+58.240 s of 5.96(-1.06, +1.09)x10^-6 erg/cm2/s (both in the 20 keV - 10 MeV energy range). The time-integrated spectrum of the burst (from T0 to T0+145.664 s) can be fitted (in the 20 keV - 10 MeV range) by GRB (Band) model for which: the low-energy photon index alpha = -0.96(-0.09, +0.12), the high energy photon index beta = -2.09(-0.22, +0.16), the peak energy Ep = 416(-73, +76) keV (chi2 = 104.0/89 dof). All the quoted errors are at the 90% confidence level. Assuming z = 3.6 (Chornock et al., GCN 9028) and a standard cosmology model with H_0 = 70 km/s/Mpc, Omega_M = 0.27, Omega_\Lambda = 0.73, the isotropic energy release E_iso ~5.6x10^54 erg, the peak luminosity (L_iso)_max ~ 7.6x10^53 erg/s, and Ep_rest ~1900keV. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB090323_T00174/
GCN 9031 table
GRB_name GRB090323A
GCN_number 9031
Detection_method Swift-XRT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 9031 SUBJECT: GRB 090323: Swift-XRT refined analysis DATE: 09/03/24 16:53:38 GMT FROM: Matteo Perri at ISAC/ASDC M. Perri and G. Stratta (ASDC) report on behalf of the Swift-XRT team: We have analysed the first 6 ks of Swift-XRT data of the Fermi GRB 090323 (Ohno et al., GCN Circ. 9021). The data, starting at 2009-03-23 19:27:51 UT and ending at 2009-03-24 09:47:02 UT, is all taken in Photon Counting (PC) mode. The X-ray source reported by Kennea et al. (GCN Circ. 9024) is found to be fading and we thus confirm that it was the afterglow of GRB 090323. In the time interval T+70 ks-T+121 ks the X-ray light-curve can be modelled by a simple power law with a decay index alpha=2.1 (+0.9)(-0.7). The X-ray spectrum is well fit by an absorbed power-law model with a photon index of 2.2 (+/-0.4) and a column density consistent with the Galactic one in the direction of the source (1.7e20 cm**-2, Kalberla et al. 2005). The estimated 3-sigma (2-sigma) upper limit on the intrinsic column density at z=3.6 (Chornock et al., GCN Circ. 9028) is 5.1e22cm**-2 (2.7e22cm**-2). All the quoted errors are at the 90% confidence level. Assuming the X-ray emission continues to decline at the same rate, we predict a 0.3-10 keV XRT count rate of 5e-3 count/s at T+48hr, which corresponds to an observed 0.3-10 keV flux of ~2e-13 erg/cm**2/s. This circular is an official product of the Swift-XRT Team.
GCN 9032 table
GRB_name GRB090323A
GCN_number 9032
Detection_method Optical
ra 190.7095°
decl 17.0533°
Circular_text TITLE: GCN CIRCULAR NUMBER: 9032 SUBJECT: GRB 090323: UVOT Detection of Afterglow DATE: 09/03/24 19:40:58 GMT FROM: Erik Hoversten at Swift/Penn State E. A. Hoversten (PSU) reports on behalf of the Swift UVOT team: The Swift/UVOT began settled observations of the field of GRB 090323 70 ks after the Fermi LAT trigger (Ohno et al., GCN 9021). The afterglow is detected in the UVOT white filter at: RA (J2000) 12:42:50.29 Dec (J2000) 17:03:11.8 with an estimated uncertainty of 0.8 arcsec (radius, 90% confidence). This position is consistent with the UVOT enhanced XRT position (Kennea et al., GCN 9024) as well as the optical position determined by GROND (Updike et al., GCN 9026) The afterglow candidate does not appear in the DSS images. Photometry from the second set of Swift observations may be indicative of fading, but is not deep enough to be conclusive. UVOT magnitudes and 3-sigma upper limits are reported in the following table: Filter T_start T_stop Exp(s) Mag (3-sigma upper limit) ----------------------------------------------------- WHITE 70287 75931 1196 21.66 +/- 0.28 WHITE 115572 121460 601 > 21.60 V 70667 76062 517 > 19.88 U 69906 75078 1200 > 21.02 The quoted upper limits have not been corrected for the expected Galactic extinction along the line of sight of E(B-V) = 0.03 mag. All photometry is on the UVOT photometric system described in Poole et al. (2008, MNRAS, 383, 627).
GCN 9033 table
GRB_name GRB090323A
GCN_number 9033
Detection_method Fermi GBM Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 9033 SUBJECT: GRB 090323 TLS detection - still bright DATE: 09/03/25 00:42:02 GMT FROM: Alexander Kann at TLS Tautenburg D. A. Kann, U. Laux and B. Stecklum (TLS Tautenburg) report: We observed the afterglow (Updike et al., GCN 9026, Cenko et al. GCN 9027) of the intense Fermi GBM/LAT GRB 090323 (Ohno et al., GCN 9021) with the 1.34m Schmidt telescope of the TLS Tautenburg observatory under inclement conditions (low transparency, passing clouds). We obtained 8 Rc frames of 600 seconds exposure time each before clouds shut us down. The afterglow is faintly detected in each single image and clearly detected in the complete stack. Assuming the star at RA = 12 42 39.3, Dec. = +17 05 05.7 to have Rc = 17.15 (USNOR1=17.17, USNOR2=17.12), we measure the following afterglow magnitude: days after trigger Rc dRc (statistical) 1.87751 20.88 0.04 This value is only slightly fainter than those reported ~18 hours earlier (Updike et al., GCN 9026, Cenko et al. GCN 9027), which may indicate the following: - The afterglow is undergoing a plateau phase or possibly even a rebrightening (if it faded more inbetween). - The magnitude of the comparison star is highly incorrect (e.g., variable star). But we also used several other comparison stars and find agreement within +/- 0.2 mags. If the afterglow truly is this bright, this makes it one of the most luminous afterglows every detected, comparable or even exceeding the recent GRB 090313 (Perley et al., GCN 8985, de Ugarte Postigo et al., 8992). The very low foreground extinction, excellent observability, low influence of moonlight combined with the extreme high energy properties (possible several ksec long tail emission in LAT, Ohno et al., GCN 9021, extremely high isotropic energy release, Golenetskii et al., GCN 9030) and the spectroscopic redshift (Chornock et al., GCN 9028) make this a GRB of special interest, and more observations, especially with medium-size telescopes, are encouraged. If weather permits, Tautenburg will continue observations. This message may be cited.
GCN 9034 table
GRB_name GRB090323A
GCN_number 9034
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 9034 SUBJECT: GRB 090323: Optical observation of xinglong TNT DATE: 09/03/25 02:16:34 GMT FROM: L.P. Xin at NAOC X.F. Wang, L.P. Xin, W.K. Zheng, Y.L. Qiu, J.Y. Wei, j. Wang, J.S. Deng and J.Y. Hu on behalf of EAFON report: We have observed GRB090323 (Ohno et al.GCN 9021; Updike et al.GCN 9026; Cenko et al. GCN 9027) with Xinglong TNT telescope from Mar.24,14:51:14(UT), 38.8 hr after the burst. After combined 10*600s R band images, the optical afterglow was detected about R=20.55 mag at the mean time of 1.651 days after the trigger, with the same calibration star (RA = 12 42 39.3, Dec. = +17 05 05.7, Rc=17.15) of kann et al., (GCN 9033). Further observation is suggested, for the late slowly decay of the optical afterglow. This message may be cited. For more information about Xinglong GRBs Follow-up observations, please visit the website: http://www.xinglong-naoc.org/grb/
GCN 9035 table
GRB_name GRB090323A
GCN_number 9035
Detection_method Fermi GBM Other
redshift 3.5700
Circular_text TITLE: GCN CIRCULAR NUMBER: 9035 SUBJECT: GRB 090323: Fermi GBM Spectral Analysis DATE: 09/03/25 03:11:27 GMT FROM: Alexander van der Horst at NASA/MSFC A.J. van der Horst (NASA/MSFC/ORAU) reports on behalf of the Fermi GBM team: "We have performed spectral analysis of the GBM data for GRB 090323 (GCN 9021). The analysis was restricted to the first ~70 seconds of GRB emission, because after that time the Fermi Observatory executed a maneuver following this bright GRB, which caused rapid, significant changes in the source angles of the various detectors and in the background behaviour. The spectrum from T0-2.0 s to T0+71.7 s is best fit by a power-law function with a high-energy exponential cutoff. The power-law index is -0.89 +/- 0.03, and the cutoff energy, parameterized as Epeak, is 697 +/- 51 keV (chi squared 379.4 for 359 d.o.f.). At a redshift of 3.57 (GCN 9028), the Epeak in the GRB rest frame, Epeak_rest, is 3.19 +/- 0.23 MeV. The event fluence (8-1000 keV) in this time interval is (1.00 +/- 0.01)E-4 erg/cm^2. The 1-sec peak photon flux measured starting from T0+65.5 s in the 8-1000 keV band is 12.3 +/- 0.4 ph/s/cm^2. This time interval consists of two main emission peaks, from T0-2.0 s to T0+33.8 s and from T0+33.8 s to T0+71.7 s. Both of these shorter intervals are also best fit by a power-law function with a high-energy exponential cutoff. For the first interval the power-law index is -1.00 +/- 0.03, Epeak is 1173 +/- 175 keV, Epeak_rest is 5.36 +/- 0.80 MeV, and the fluence (8-1000 keV) is (3.68 +/- 0.06)E-5. For the second interval the power-law index is -0.83 +/- 0.03, Epeak is 574 +/- 34 keV, Epeak_rest is 2.62 +/- 0.16 MeV, and the fluence (8-1000 keV) is (6.35 +/- 0.09)E-5. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
GCN 9036 table
GRB_name GRB090323A
GCN_number 9036
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 9036 SUBJECT: GRB 090323: Lick observations DATE: 09/03/25 10:43:03 GMT FROM: Daniel Perley at U.C. Berkeley D. A. Perley, C. R. Klein, A. N. Morgan, and E. Petigura (UC Berkeley) report: We observed the afterglow of GRB 090323 (Ohno et al., GCN 9021; Updike et al., GCN 9026; Cenko et al., GCN 9027) with the Nickel 40in telescope at Lick Observatory starting at UT 06:45 on 2009-03-25 for a series of 5- and 10- minute exposures totaling 55 minutes of integration time under photometric conditions. The afterglow is detected in the stacked frame. Using the same calibration star mentioned in Kann et al. (GCN 9033), we calculate a magnitude of R = 21.3 +/- 0.2 at a mid-time of t=2.30 days after the trigger. This suggests (within the uncertainty) that the afterglow has faded significantly since the observations of Kann et al. and Wang et al. (GCN 9034) ~12 hours prior and that the optical flattening phase may have ended. Additional observations are planned.
GCN 9037 table
GRB_name GRB090323A
GCN_number 9037
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 9037 SUBJECT: GRB 090323: RTT150 optical observations DATE: 09/03/25 12:22:37 GMT FROM: Rodion Burenin at IKI, Moscow R. Burenin, A. Tkachenko, M. Pavlinsky, R. Sunyaev (IKI), I. Khamitov, Z. Eker (TUG), U. Kiziloglu (METU), E. Gogus (Sabanci Uni.), I. Bikmaev, N. Sakhibullin (KSU/AST) report: The optical afterglow of GRB 090323 (Updike et al., GCN 9026, Cenko et al., GCN 9027) was observed with Russian-Turkish 1.5-m telescope (RTT150, Bakirlitepe, TUBITAK National Observatory, Turkey). We obtained 6x600s exposures in sdss-r filter, centered at March 25, 01:30 UT, i.e. 2.059 days after the burst. The afterglow is detected in all frames. Using the same calibration star as it was used by Kann et al. (GCN 9033), we esimate the magnitude of the OT as R=20.85+-0.04. During our observations we also marginally detected gradual decline of the afterglow brightness at a rate of approximately 0.3 mag/hour, which is steeper than that assumed by the comparison with the data obtained by Perley et al. (GCN 9036). Our light curve and finding chart can be found at: http://hea.iki.rssi.ru/grb/090323/indexeng.html
GCN 9039 table
GRB_name GRB090323A
GCN_number 9039
Detection_method Fermi GBM Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 9039 SUBJECT: GRB 090323: Faulkes Telescope South Observations DATE: 09/03/26 10:11:36 GMT FROM: Cristiano Guidorzi at Ferrara U,Italy C. Guidorzi (U. Ferrara), I. A. Steele, A. Melandri, D. Bersier (Liverpool JMU), A. Gomboc (U. Ljubljana), S. Kobayashi, C.J. Mottram, C.G. Mundell, R.J. Smith (Liverpool JMU), P. O'Brien, N. Bannister, N. Tanvir (U. Leicester) on behalf of a large collaboration report: The 2-m Faulkes Telescope South (Siding Spring, Australia) began observing the afterglow (Updike et al., GCN Circ. 9026; Cenko et al., GCN Circ. 9027) of the Fermi GBM/LAT GRB 090323 (Ohno et al., GCN Circ. 9021; van der Horst et al., GCN Circ. 9035) on March 25, 11:50:55 UT, i.e. at 2.49 days post burst. Observations were carried out in filters R and i. The afterglow is clearly detected in both filters with the following magnitudes: Filter Tmid(days) Exposure(s) Mag ------------------------------------------------- i 2.50 6x300 21.3 +/- 0.2 R 2.53 6x300 21.7 +/- 0.1 ------------------------------------------------- Magnitudes are calibrated with respect to nearby SDSS stars. Comparing with previous reports (Kann et al., GCN Circ. 9033; Wang et al., GCN Circ. 9034; Perley et al., GCN Circ. 9036; Burenin et al., GCN Circ. 9037) we confirm the steepening of the decay.
GCN 9041 table
GRB_name GRB090323A
GCN_number 9041
Detection_method Fermi GBM Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 9041 SUBJECT: GRB 090323: TLS detection at 5 days, no break DATE: 09/03/28 04:23:25 GMT FROM: Alexander Kann at TLS Tautenburg D. A. Kann, U. Laux and B. Stecklum (TLS Tautenburg) report: We observed the afterglow (Updike et al., GCN 9026, Cenko et al. GCN 9027) of the intense Fermi GBM/LAT GRB 090323 (Ohno et al., GCN 9021) with the 1.34m Schmidt telescope of the TLS Tautenburg observatory under decent conditions (low transparency). We obtained 11 Rc frames of 600 seconds exposure time each before dawn shut us down. The afterglow is faintly detected in some single images and well-detected in the complete stack. Using the same comparison star as Kann et al. (GCN 9033), we measure the following afterglow magnitude: days after trigger Rc dRc (statistical) 5.10418 22.67 0.20 Using other published data (Updike et al., GCN 9026, Wang et al., GCN 9034, Perley et al. GCN 9036, Guidorzi et al., GCN 9039) as well as additional TLS data from the first observation run, we find that all data agree decently well with a single power law decay with a slope alpha ~ 1.8. Therefore, there does not seem to be a plateau phase, but there is also no sign of a break yet. The relatively steep decay makes it unclear if this is a steep pre-break decay slope or a shallow post-break decay slope. In the latter case, it will be possible to track the afterglow for a very long time. Further deep, high S/N observations with larger telescopes are advised. This message may be cited.
GCN 9042 table
GRB_name GRB090323A
GCN_number 9042
Detection_method Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 9042 SUBJECT: GRB 090323: Additional Lick observations DATE: 09/03/28 06:28:09 GMT FROM: Daniel Perley at U.C. Berkeley D. A. Perley (UC Berkeley) reports: On the night of 2009-03-27 (UT) I returned to the location of the afterglow of GRB 090323 (Updike et al., GCN 9026; Cenko et al., GCN 9027) with the Nickel 40-inch telescope at Lick Observatory and acquired an additional series of 900s R-band exposures between 05:12 and 12:26 UT totaling 260 minutes of integration time. While not clearly visible in individual exposures, the afterglow is detected in stacked frames. Using the calibration star of Kann et al. (GCN 9033), I measure a magnitude of R = 22.63 +/- 0.18 at an observation mid-point of t = 4.36 days in a stack of all observations throughout the night, consistent with the absence of a break in the light curve reported by Kann et al. (GCN 9041). I thank Mo Ganeshalingam for the exchange of observing time.
GCN 9043 table
GRB_name GRB090323A
GCN_number 9043
Detection_method Optical
ra 190.7096°
decl 17.0533°
Circular_text TITLE: GCN CIRCULAR NUMBER: 9043 SUBJECT: GRB 090323: Radio afterglow detection DATE: 09/03/28 22:57:52 GMT FROM: Dale A. Frail at NRAO F. Harrison (Caltech), B. Cenko (UC Berkeley), D. A. Frail (NRAO), P. Chandra (RMC), and S. Kulkarni (Caltech) report: "We observed the field centered at the optical afterglow (GCN Circ. 9026) of the Fermi GBM/LAT GRB 090323 (GCN Circ. 9021, GCN Circ. 9035) on March 27.38 UT using the Very Large Array (VLA) at a frequency of 8.46 GHz. We detect an unresolved radio source at the GRB afterglow position with the flux density of 225+/-35 uJy at a (J2000) position of: RA = 12h 42m 50.292s DEC = +17d 03' 11.90" with an uncertainty of 0.05" Further observations are planned. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc."
GCN 9047 table
GRB_name GRB090323A
GCN_number 9047
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 9047 SUBJECT: GRB 090323: WSRT Radio Detection DATE: 09/03/29 11:01:03 GMT FROM: Alexander van der Horst at NASA/MSFC A.J. van der Horst (NASA/MSFC/ORAU) reports on behalf of a large collaboration: "We observed the position of the GRB 090323 afterglow at 4.9 GHz with the Westerbork Synthesis Radio Telescope at March 27 17.92 UT to March 28 5.91 UT, i.e. 4.74 - 5.24 days after the burst (GCN 8980). We detect a radio source with a flux density of 105 +/- 24 microJy at the position of the optical counterpart (GCN 9021). We would like to thank the WSRT staff for scheduling and obtaining these observations."
GCN 9051 table
GRB_name GRB090323A
GCN_number 9051
Detection_method Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 9051 SUBJECT: GRB090323: Optical observations from NOT DATE: 09/03/29 20:21:03 GMT FROM: Antonio Deugarte at IAA-CSIC A. de Ugarte Postigo (ESO), D. Xu, D. Malesani, J. Hjorth, J.P.U. Fynbo (DARK/NBI), P. Jakobsson (Univ. of Iceland), A. Adamo, G. Micheva (Stockholm Univ.) on behalf of a larger collaboration report: We have observed the field of GRB 090323 (Ohno et al. GCN 9021) with the 2.5m NOT telescope (+ALFOSC) at Roque de los Muchachos Observatory (Spain). The mean epoch of our observations is March 29.323 UT (6.327 days after the burst). The afterglow (Kennea et al. GCN 9024, Updike et al. GCN 9026) is clearly detected in the 6x300s combined exposure with R=22.80+/-0.06. As photometric reference we used the object indicated by Kann et al. (GCN 9033). Our measurement is consistent with the absence of a light curve steepening, as noted one day earlier by Kann et al. (GCN 9041). A lightcurve composed of GCN data together with our observation shows a possible flattening during the last 3 days. Further observations are foreseen. [GCN OPS NOTE(29mar09): Per author's request, GM was added to the author list.]
GCN 9063 table
GRB_name GRB090323A
GCN_number 9063
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 9063 SUBJECT: GRB 090323: Further TLS detections - a break? DATE: 09/04/01 02:22:46 GMT FROM: Alexander Kann at TLS Tautenburg D. A. Kann, U. Laux, F. Ludwig and B. Stecklum (TLS Tautenburg) report: We observed the afterglow (Updike et al., GCN 9026, Cenko et al. GCN 9027) of the intense Fermi GBM/LAT GRB 090323 (Ohno et al., GCN 9021) with the 1.34m Schmidt telescope of the TLS Tautenburg observatory at several epochs. At ~6 days after the GRB, conditions were bad (low transparency and passing clouds). We obtained 21 Rc frames of 600 seconds exposure time each. Only four of these are usable. The afterglow is faintly detected in the complete stack. Using the same comparison star as Kann et al. (GCN 9033), we measure the following afterglow magnitude: days after trigger Exposure Rc dRc (statistical) 5.89127 4 x 600 23.13 0.50 At ~7 days after the GRB, conditions were very bad (almost complete overcast). We obtained 1 Rc frames of 600 seconds exposure time which had good quality. The afterglow is not detected. days after trigger Exposure Rc 6.99881 1 x 600 > 22.50 This limit is not constraining. At ~9 days after the GRB, conditions were very good (good transparency, good seeing, but influence of moonlight). We obtained 12 Rc frames of 600 seconds exposure time each. The afterglow is faintly detected in the complete stack. days after trigger Exposure Rc dRc (statistical) 8.90324 12 x 600 23.64 0.36 Compared to the flattening of the decay noted by de Ugarte Postigo et al. (GCN 9051) and already hinted at in earlier TLS and Lick data (Kann et al., GCN 9041, Perley, GCN 9042), the decay has steepened again, an indication of a (jet?) break. On the other hand, the last TLS detection agrees well with the extrapolation of the earlier decay (Kann et al., GCN 9041), indicating that the plateau may be a rebrightening/optical flare spanning a few days. Due to increasing moonlight, no further TLS observations are planned. This message may be cited.
GCN 9324 table
GRB_name GRB090323A
GCN_number 9324
Detection_method Optical
ra 12.0000°
decl 17.0000°
Circular_text TITLE: GCN CIRCULAR NUMBER: 9324 SUBJECT: GRB 090323: optical observations DATE: 09/05/05 00:46:36 GMT FROM: Alexei Pozanenko at IKI, Moscow V. Rumyantsev (CrAO), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration: We observed the afterglow (Updike et al., GCN 9026; Cenko et al., GCN 9027) of Fermi GRB 090323 (GBM trigger 259459364 / 090323002; Ohno et al., GCN 9021) on Apr. 28 and Apr. 29 with Shajn telescope of CrAO. We clearly detect the afterglow in R and do not detect in I- filter. Astrometry of the afterglow is RA(J2000): 12 42 50.29 Dec(J2000): +17 03 11.98 with uncertainty of 0.2 arcsec is compatible with reported in GCN 9026. A photometry of combined images based on USNO-B1.0 star RA=12:42:39.3 Dec=+17:05:05.7 (previously used by Kann et al. GCN 9033) is following: T0+ Filter, Exposure, mag., err. Seeing (d) (s) 5.9934 R 91x60 22.7 +/- 0.1 1.6" 6.8990 I 84x60 >22.4 (3sigma) 2.9" The combined image of the observation on Apr. 28 can be found at http://grb.rssi.ru/GRB090323/GRB090323_R_ZTSh_090328.gif Our photometry in R is compatible with estimations obtained in nearby epochs (Kann et al. GCN 9041, de Ugarte Postigo et al. GCN 9051) and confirms the flattening of the light curve mentioned by de Ugarte Postigo et al. (GCN 9051). The non-detection of the afterglow in I-filter in second epoch of our observation (T0+6.899 d) tentatively supports the steepening of light curve discussed by Kann et al. (GCN 9063). Indeed the upper limit I > 22.4 is translating into R > 22.8 provided the color index R-I ~ 0.4 obtained from observations of Updike et al. (GCN 9026) and Guidorzi et al. (GCN 9039) is not changing along late time light curve.