Gamma-ray Burst 080514B

(All information courtesy of the instrument teams.)

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Results of Observations

GCN Circular #7715
Subject: GRB 080514B: SuperAGILE/IPN GRB Localization
M. Rapisarda, E. Costa, E. Del Monte, I. Donnarumma, Y. Evangelista, M. Feroci, I. Lapshov, F. Lazzarotto, L. Pacciani, P. Soffitta, (INAF/IASF Rome), A. Giuliani, S. Vercellone, A. Chen, S. Mereghetti, A. Pellizzoni, F. Perotti, F. Fornari, M. Fiorini, P. Caraveo (INAF/IASF Milan), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), M. Tavani, G. Pucella, F. D'Ammando, V. Vittorini, A. Argan, A. Trois (INAF/IASF Rome), G. Barbiellini, F. Longo (INFN Trieste), P. Cattaneo (INFN Pavia), P. Picozza, A. Morselli (INFN Roma-2), M. Prest, E. Vallazza (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), and P. Giommi, C. Pittori, B. Preger, F. Verrecchia (ASDC) and L. Salotti (ASI), on behalf of the AGILE Team,
K. Hurley, on behalf of the Mars Odyssey team,
I. G. Mitrofanov, D. Golovin, M. L. Litvak, and A. B. Sanin, on behalf of the HEND-Odyssey GRB team, and
W. Boynton, C. Fellows, K. Harshman, C. Shinohara and R. Starr, on behalf of the GRS-Odyssey GRB team,
report:
"SuperAGILE and AGILE/MCAL detected a gamma ray burst on May 14th, at 09:55:56 UT. The event was localized by SuperAGILE at approximately 38 degrees off axis, in the one-dimensional portion of its field of view, thus providing a narrow and long error box. The narrow side is 6 arcmin wide, while the long side is approximately 40 degrees wide. In the 20-60 keV energy range the event had a 10s duration, with a multi-peaked structure.
The same event was also detected by Mars Odyssey. The IPN was thus able to reduce the SuperAGILE error box to the 100 sq arcmin error box whose corners are given by the following coordinates (RA, Dec):
```
  322.962 (21h 31m 50.81s)       0.733  (0d 43m 59.69s)
  322.774 (21h 31m  5.74s)       0.667  (0d 40m  2.78s)
  322.867 (21h 31m 27.99s)       0.806  (0d 48m 21.16s)
  322.678 (21h 30m 42.80s)       0.740  (0d 44m 23.63s)
```
The centroid of the error box is at (RA, Dec)= (322.820, 0.737) and the maximal distance between the box corners is 0.283 deg, that is 16.9 arcmin.
The event occurred in the field of view of the AGILE GRID. A report on the AGILE/GRID data analysis will follow shortly.
We urge follow-up observations at all wavelengths."
This message may be cited.
GCN Circular #7716
SUBJECT: GRB 080514B: possible AGILE detection at E>50 MeV
A. Giuliani, F. Fornari, S. Mereghetti, S. Vercellone, A. Chen, A. Pellizzoni, F. Perotti, M. Fiorini, P. Caraveo, A. Zambra (INAF/IASF Milan), P. Soffitta, I. Donnarumma, E. Del Monte, M. Feroci, Y. Evangelista, E. Costa, I. Lapshov, F. Lazzarotto, L. Pacciani, M. Rapisarda (INAF/IASF Rome), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli, (INAF/IASF Bologna), M. Tavani, G. Pucella, F. D'Ammando, V. Vittorini, A. Argan, A. Trois (INAF/IASF Rome), G. Barbiellini, F. Longo (INFN Trieste), G. De Paris, P. Picozza, A. Morselli (INFN Roma-2), M. Prest, E. Vallazza (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), and P. Giommi, C. Pittori, (ASDC) and L. Salotti (ASI), on behalf of the AGILE Team, report:
"A quick look analysis of the AGILE GRID data of GRB 080514B (Rapisarda et al. GCN 7715) shows a possible detection at energies E>50 MeV at a position consistent with the SuperAGILE-IPN localization.
We have requested a ToO observation of the SuperAGILE-IPN error box with the Swift satellite. We encourage follow-up observations at other wavelengths."
This message may be cited.
GCN Circular #7718
P. Kubanek (IAA-CSIC, GACE), J. French (UCD), A. de Ugarte Postigo (ESO) report on behalf of a larger colaboration:
The 0.4m WATCHER telescope located at Boyden Observatory, South Africa, has observed the field of GRB 080514B (Rapisarda et al., GCN 7715) starting at May 15.042 UT (~15.1 hours after the burst) in a sequence of 120s R band exposures. A combined image covering ~90% of the error box does not show any new source down to a limiting magnitude of R>19 at a mean epoch of May 15.076 UT.
Further analysis is ongoing.
GCN Circular #7719
A de Ugarte Postigo (ESO), A. Castro-Tirado, J. Gorosabel, M. Jelinek (IAA-CSIC), P. Kubanek (IAA-CSIC, GACE) A. Garcia, A. Pimienta, E. Curras (IAC), C. Pereira (Armagh Obs.), on behalf of a larger collaboration report:
We have observed the error box of GRB080514B (Rapisarda et al., GCN 7715) from the 0.8m IAC80 telescope at Iza� Observatory (Spain) in I-band starting on May 15.133 (17.3 hours after the burst) There is a source with a mag of I~20.4, not present in the SDSS-i at the following coordinates (J2000 +/-1"):
```
R.A.: 21:31:22.69
Dec.: +00:42:28.9
```
Further observations are encouraged to confirm if this is related to the GRB.
GCN Circular #7720
A de Ugarte Postigo (ESO), A. Castro-Tirado, J. Gorosabel, M. Jelinek (IAA-CSIC), P. Kubanek (IAA-CSIC, GACE) A. Garc�, A. Pimienta, E. Curras (IAC), C. Pereira (Armagh Obs.), on behalf of a larger collaboration report:
A finding chart of the optical candidate of GRB 080514B (Rapisarda et al., GCN 7715) reported in GCN 7719, compared to the SDSS-i frame can be found at: http://www.sc.eso.org/~adeugart/GRB/080514B/GRB080514B.jpg
GCN Circular #7722
A. Rossi (Tautenburg), A. Kupcu-Yoldas, J. Greiner (MPE Garching), S. Klose, R. Filgas (Tautenburg), A. Yoldas, T. Kruehler (MPE), and G. Szokoly (Eoetvoes Univ. Budapest and MPE) report on behalf of the GROND team:
We observed the field of GRB 080514B (Rapisarda et al., GCN 7715; Giuliani et al., GCN 7716) simultaneously in g'r'i'z'JHK using the multi-channel imager GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2m MPI/ESO telescope on La Silla (Chile). Observations started at 7:03 UT, about 21 h after the burst.
The afterglow candidate reported by de Ugarte Postigo et al. (GCN 7719) is detected in g'r'i'z'. Preliminary photometry yields g' = 19.95 +/- 0.2, calibrated against NOMAD field stars. Observations are ongoing.
We thank Antonio de Ugarte Postigo (ESO) for a rapid communication of the finding chart.
GCN Circular #7723
K.L. Page, A.P. Beardmore (U. Leicester), S. Mereghetti (INAF - IASF Milano), M. Feroci and M. Tavani (INAF/IASF Roma) report on behalf of the Swift-XRT and AGILE teams:
Following a ToO request, Swift-XRT started observing the field of GRB 080514B at 20:12 on 14th May, about 37 ks after the trigger. Within the SuperAGILE/IPN error box, there are two sources detected, one of which is much brighter and appears to be fading. We therefore believe this to be the X-ray afterglow of the GRB.
Using 925 s of overlapping XRT Photon Counting mode and UVOT data, 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 = 322.84426, 0.70843 which is equivalent to:
```
RA (J2000):   21 31 22.62
Dec (J2000): +00 42 30.3
```
with an uncertainty of 1.6 arcsec (radius, 90% confidence). This position is 1.7 arcsec from the i-filter object mentioned by de Ugarte Postigo et al., in GCN Circ. 7719.
A spectrum of the three orbits of Photon Counting (PC) mode data (6 ks of data, spanning 37-49 ks after the trigger) can be modelled with an absorbed power-law of Gamma = 2.06 +0.35/-0.31 and NH = (1.2 +0.8/-0.6)x10^21 cm^-2, which is slightly in excess of the Galactic value of 3.75x10^20 cm^-2. The observed (unabsorbed) 0.3-10 keV flux is 2.34x10^-12 (3.14x10^-12) erg cm^-2 s^-1. This corresponds to an observed counts to flux conversion of 1 count = 3.96x10^-11 erg cm^-2.
The light-curve can be fitted with a single power-law, with a slope of alpha = 1.5 +/- 1.0. If the light-curve continues to follow this decay, the count rate at 48 hours is predicted to be 6.6x10^-3 count s^-1 (an observed flux of 2.6x10^-13 erg cm^-2 s^-1).
This circular is an official product of the Swift-XRT team.
GCN Circular #7724
A. Rossi (Tautenburg), A. Kupcu-Yoldas, J. Greiner (MPE Garching), S. Klose, R. Filgas (Tautenburg), A. Yoldas, T. Kruehler (MPE), and G. Szokoly (Eoetvoes Univ. Budapest and MPE) report on behalf of the GROND team:
We continued observing the field of GRB 080514B (Rapisarda et al., GCN 7715; Giuliani et al., GCN 7716) simultaneously in g'r'i'z'JHK using the multi-channel imager GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2m MPI/ESO telescope on La Silla (Chile).
We detect a very slow fading behaviour in the afterglow brightness. The i' band magnitude dropped ~0.05 magnitudes within 1.5 hours, resulting in i'~20.9 around 08:20 UT. This magnitude is ~0.5 magnitudes fainter than the i-band magnitude given by Ugarte et al. (GCN 7719).
Please note that the g' magnitude mentioned in GCN 7722 has a typo; it should be g' = 21.2.
GCN Circular #7725
Adria C. Updike, Ginger Bryngelson, and Dieter H. Hartmann (Clemson University) report on behalf of the Clemson GRB Follow-Up Team:
We observed GRB 080514B (Hurley et al., GCN 7715) using the KPNO 4m telescope and the NEWFIRM NIR imager under decent weather conditions. In 4 min of stacked exposures beginning 24 hours and 20 minutes after the trigger, we detect the afterglow (Postigo et al., GCN 7719) at J = 19.8 +/- 0.2 (as calibrated to the 2MASS catalog). Observations are ongoing.
This message may be cited.
GCN Circular #7730
B. Gendre (LAM/CNRS/Universite de Provence), A. Galli (IASF-Roma/INAF), M. Bo� (OHP/CNRS) report :
Using the XRT analysis reported by Page et al. (GCN 7723), we extrapolated an X-ray flux of 4.8 10^-13 cgi 1 day after the burst (2-10 keV). Using the Boer & Gendre relation, we estimate the redshift of GRB 080514B to be either 2.8 or 0.9 if this event is a group I or II respectively (see Gendre, Galli & Bo�, ApJ, in press), with uncertainties of 30%. Further constraints on the redshift could be set by B observations of the afterglow candidate reported in de Ugarte Postigo et al. (GCN 7719).
This message can be cited.
GCN Circular #7734
D. Malesani (DARK/NBI), P.E. Nissen (Univ. Aarhus), W.J. Schuster (UNAM), and J.P.U. Fynbo (DARK/NBI), report on behalf of a larger collaboration:
We observed the afterglow of GRB 080514B (Rapisarda et al., GCN 7715; Giuliani et al., GCN 7716; de Ugarte Postigo et al., GCN 7719) with the NOT equipped with ALFOSC. Observations were carried out with the B, R and I filters.
We clearly detect the afterglow in all bands. On mean time May 16.184 UT (1.77 days after the trigger), we measure R = 22.52 +- 0.10 (AB), calibrated against SDSS r magnitudes. The detection in B implies a redshift limit z < 3.7.
GCN Circular #7745
Adria C. Updike, Ginger Bryngelson, and Dieter H. Hartmann (Clemson University) report on behalf of the Clemson GRB Follow-Up Team:
We re-imaged the field of GRB 080514B (Hurley et al., GCN 7715) with the KPNO 4m + NEWFIRM under good weather conditions. We obtained 15 minutes in the J and H bands approximately 48 hours after the trigger. In stacked images, we marginally detect the afterglow (Postigo et al., GCN 7719) at J = 20.7 +/- 0.3 (calibrated to the 2MASS catalog). We do not detect the afterglow in the H band with a limiting magnitude of 20.2.
This message may be cited.
GCN Circular #7750
P. Esposito, A. De Luca, A. Tiengo, G. Vianello (INAF-IASF MI), K.L. Page (U. Leicester) report:
GRB 080514B was discovered by the SuperAGILE detector on May 14th, at 09:55:56 UT (Rapisarda et al., GCN Circ. 7715) and possibly detected at energies E>50 MeV in AGILE GRID data (Giuliani et al., GCN Circ. 7716).
The first Swift/XRT observation was performed on May 14th at 20:12, starting about 37 ks after the GRB trigger (Page et al., GCN Circ. 7723). A likely afterglow candidate was found, with a flux decay described by a power-law (slope: 1.5+/-1.0; GCN Circ. 7723). The spectrum was modelled with an absorbed ( 1.2x10^21 cm^-2) power-law, with photon index = 2.06 (GCN Circ. 7723).
Swift/XRT observed again the field of GRB 080514B on May 16th at 20:13, about 58 hours after the trigger. 6 ks of data in Photon Counting mode were collected in three consecutive orbits, spanning 5 hours.
The candidate X-ray afterglow (GCN Circ. 7723) is significantly detected with a 0.3-10 keV observed flux of (1.9+/-0.8)x10^-13 erg cm^-2 s^-1 (assuming the spectrum of Circ. 7723).
The new XRT data confirm the fading trend reported in (GCN Circ. 7723) and better constrain the decay slope at 1.6 +0.3/-0.2.
We thank the Swift PI, N. Gehrels, for approval of this TOO, and the Swift team (in particular the duty scientists and science planners) for performing it.
GCN Circular #7751
S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, and T. Cline on behalf of the Konus-Wind team report:
The bright GRB 080514B localized by SuperAGILE/IPN (Rapisarda et al., GCN 7715) triggered Konus-Wind at T0=35758.672 s UT (09:55:58.672).
The burst light curve shows a multipeaked structure with a duration of ~7 s.
As observed by Konus-Wind the burst had a fluence of 3.23(-0.26, +0.27)x10^-5 erg/cm2, and a 16-ms peak flux measured from T0+3.328 s of (2.07 +/- 0.43)x10^-5 erg/cm2/s (both in the 20 keV - 5 MeV energy range).
The time-integrated spectrum of the burst (from T0 to T0+12.032 s) is well fitted (in the 20 keV-5 MeV range) by GRBM (Band) model for which: the low-energy photon index is alpha = -0.599(-0.134, +0.161), the high energy photon index beta = -2.48(-0.25, +0.18), the peak energy Ep = 224 (-22, +23) keV (chi2 = 72.3/76 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.rssi.ru/LEA/GRBs/GRB080514_T35758/
GCN Circular #7752
Y. Hanabata, T. Uehara, Y. Fukazawa, T. Takahashi, C. Kira (Hiroshima U.), M. Ohno, M. Kokubun, M. Suzuki, T. Takahashi (ISAS/JAXA), K. Yamaoka, S. Sugita (Aoyama Gakuin U.), K. Onda, M. Tashiro, Y. Terada, Y. Urata, A. Endo, N. Kodaka, K. Morigami, T. Sugasahara, W. Iwakiri (Saitama U.), Y. E. Nakagawa, T. Tamagawa (RIKEN), T. Enoto, K. Nakazawa, K. Makishima (Univ. of Tokyo), E. Sonoda, M. Yamauchi, H. Tanaka, R. Hara (Univ. of Miyazaki), S. Hong (Nihon U.), on behalf of the Suzaku WAM team, report:
The long GRB 080514B, (SuperAGILE/IPN: Rapisarda et al., GCN7715 ) triggered the Suzaku Wide-band All-sky Monitor (WAM) which covers an energy range of 50 keV - 5 MeV at 09:55:57 UT (=T0). The observed light curve shows a multi-peaked structure starting at T0-1s , ending at T0+7s, with a duration (T90) of about 6.3 seconds. The fluence in 100 - 1000 keV was 1.4(+0.2,-0.1) x 10^-5 erg/cm^2. The 1-s peak flux measured from T0+2s was 11.3(+0.5,-0.1) photons/cm^2/s in the same energy range.
A preliminary result shows that the time-averaged spectrum from T0-1s to T0+7s is well fitted by a GRB Band model as follows. the low-energy photon index alpha: -1.4(+0.6,-0.5), the upper limit of the high-energy photon index beta: -2.5 and the peak energy Epeak: 259 (+43, -104) keV (chi^2/d.o.f = 27.9/23).
All the quoted errors are at statistical 90% confidence level, in which the systematic uncertainties are not included.
The light curves for this burst are available at: http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html
GCN Circular #7759
S. T. Holland (CRESST/USRA/GSFC) reports on behalf of the Swift/UVOT team:
The Swift/UVOT observed the field of GRB 080514B starting 37,005 s after the SuperAGILE/IPN detection (Rapisarda et al., GCN Circ. 7715). We detect the optical afterglow in the b, u, uvw1, and uvm2 filters at the location of the IAC80 optical afterglow (de Ugarte Postigo, et al., 2008, GCNC 7719). The UVOT source position is
```
  RA(J2000.0) =  21:31:22.71
 Dec(J2000.0) = +00:42:28.4
```
with an estimated uncertainty of +/-0.60 arcsec (radius, 90% confidence).
Magnitudes and upper limits are reported below.
```
Filter    T_start (s) T_stop  Exposure   Mag    Err  Comment
   v       38,184     43,906      352    >20.1        3-sigma UL
   b       37,449     48,630      559     20.92 0.27
   u       37,229     48,415      559     19.97 0.17
  uvw1     37,005     48,198     1118     20.74 0.24
  uvm2     38,333     44,537     1030     20.83 0.32
  uvw2     37,601     49,441     2199    >22.1        3-sigma UL
white     209,879    228,394     5360    >23.3        3-sigma UL
```
The above magnitudes and upper limits are not corrected for the Galactic extinction along the line of sight corresponding to a reddening of E_{B-V} = 0 .06 mag (Schlegel et al., 1998, ApJS, 500, 525). The photometry is on the UVOT flight system described in Poole et al. (2008, MNRAS, 383,627). The non-detections in the uvw2 filters may indicate that the redshift is z >~ 1.9.
GCN Circular #7760
A. Pelangeon & J-L. Atteia (LATT-OMP) report:
We used the spectral parameters of GRB 080514B provided by Golenetskii et al. (GCNC 7751) to compute the spectral pseudo-redshift(**) of this burst localized by SuperAGILE/IPN (Rapisarda et al., GCN 7715).
We find a pseudo-redshift pz= 1.76 0.30
We note that this redshift estimate is consistent with the observations of the afterglow in B band performed with the NOT, that may imply a redshift z < 3.7 (Malesani et al., GCNC 7734). This is also consistent with the observations of the Swift/UVOT (Holland et al., GCNC 7759), in which the non-detection of the afterglow in uvw2 filters may suggest z >~ 1.9
(**) cf. http://www.ast.obs-mip.fr/grb/pz
GCN Circular #7874
D. A. Perley, J. S. Bloom (UC Berkeley), H.-W. Chen (U Chicago), R. J. Foley, A. A. Miller, J. Shiode, J. Brewer, D. Starr, and R. Kennedy (UCB) report:
On the night of 2008-06-07 (UT) we observed the location of the Super-AGILE burst GRB 080514B (GCN 7715, Rapisarda et al.) with Keck I / LRIS in g and R filters for 1080s and 960s respectively, starting at 12:53 UT. We detect a source consistent with the afterglow position (de Ugarte Postigo et al., GCN 7719) in both filters. Photometry within a 1.1" radius aperture gives an magnitude (calibrated to three nearby USNO B1.0 stars) of:
R = 23.9 +/- 0.2 (t = 24.1 days)
Compared to the measurement of Malesani et al. (R = 22.52 at 1.77 days, GCN 7734), this would suggest a decay index of only about alpha = 0.5 were this the GRB afterglow, which is unlikely at such late times. More likely, the source represents a relatively bright host galaxy of this burst.
However, analysis of a 2x1200s Gemini-North spectrum using GMOS taken at the afterglow location (offset <0.5" from the host from a comparison from the Gemini i-band acquisition image) 1.9 days after the GRB shows no significant emission or absorption features over the usable spectral range from 4000-6720 Angstroms. The continuum flux extends all the way to 4000 Angstroms without evidence of Lyman-alpha forest absorption, which imposes a redshift constraint of z < 2.3. Further follow-up is encouraged.
A colorized image of the field is available at:
http://lyra.berkeley.edu/~dperley/080514b/080514b_color.png
0808.0151from 1 Aug 2008
Rossi: A photometric redshift of z=1.8^+0.4_-0.3 for the Agile GRB 080514B
Abstract: Aims: The AGILE gamma-ray burst GRB 080514B is the first burst with detected emission above 30 MeV and an optical afterglow. However, no spectroscopic redshift for this burst is known.
Methods: We compiled ground-based photometric optical/NIR and millimeter data from several observatories, including the multi-channel imager GROND, as well as ultraviolet \swift UVOT and X-ray XRT observations. The spectral energy distribution of the optical/NIR afterglow shows a sharp drop in the \swift UVOT UV filters that can be utilized for the estimation of a redshift.
Results: Fitting the SED from the \swift UVOT $uvw2$ band to the $H$ band, we estimate a photometric redshift of $z=1.8^{+0.4}_{-0.3}$, consistent with the pseudo redshift reported by Pelangeon & Atteia (2008) based on the gamma-ray data.
Conclusions: The afterglow properties of GRB 080514B do not differ from those exhibited by the global sample of long bursts, supporting the view that afterglow properties are basically independent of prompt emission properties.
0809.1230 from 8 Sep 2008
Giuliani: AGILE detection of delayed gamma-ray emission from GRB 080514B
Abstract: GRB 080514B is the first gamma ray burst (GRB), since the time of EGRET, for which individual photons of energy above several tens of MeV have been detected with a pair-conversion tracker telescope. This burst was discovered with the Italian AGILE gamma-ray satellite. The GRB was localized with a cooperation by AGILE and the interplanetary network (IPN). The gamma-ray imager (GRID) estimate of the position, obtained before the SuperAGILE-IPN localization, is found to be consistent with the burst position. The hard X-ray emission observed by SuperAGILE lasted about 7 s, while there is evidence that the emission above 30 MeV extends for a longer duration (at least ~13 s). Similar behavior was seen in the past from a few other GRBs observed with EGRET. However, the latter measurements were affected, during the brightest phases, by instrumental dead time effects, resulting in only lower limits to the burst intensity. Thanks to the small dead time of the AGILE/GRID we could assess that in the case of GRB 080514B the gamma-ray to X-ray flux ratio changes significantly between the prompt and extended emission phase.

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Jochen Greiner, last update: 15-Sep-2008 [Disclaimer]