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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

26310 results found.

  1. XRF 040912, identification of CXO sources
  2. XRF 040912 (=H3557): Spectral and Temporal Properties
  3. XRF040916, Ic observations
  4. XRF040916: optical follow-up observations
  5. GRB040916: Archival optical observations
  6. XRF 040916, optical follow-up
  7. GRB040912(=H3557): Observations with the Chandra X-ray Observatory
  8. ROTSE-IIIb Observations of GRB 040916 (HETE #3558)
  9. GRB040916 (= H3558): Improved Localization from HETE WXM
  10. GRB040916 (= H3558): A Long XRF Localized by HETE
  11. GRB040912 (= H3557): Chandra Observations Scheduled
  12. An intense burst from SGR1806-20
  13. GRB040912 (= H3557): A Long GRB or XRF Localized by HETE
  14. GRB040903 - A XRF?
  15. GRB040827: analysis of the XMM-Newton observation
  16. Very bright burst detected from SGR 1806-20
  17. ROTSE-III Rapid Response to possible GRB 040903 (INTEGRAL #1972)
  18. GRB 040827: optical and NIR observations at the VLT
  19. GRB 040827: UKIRT - 2nd epoch K-band imaging
  20. GRB 040827: 2nd epoch of Magellan K-band imaging
  21. GRB 040827: K imaging - no evidence of variability
  22. GRB 040827: Detection of NIR afterglow
  23. GRB 040827: RTT150 optical observations
  24. GRB040825A: optical limit before GRB
  25. GRB 040827 - A long GRB detected by INTEGRAL
  26. Increase of SGR 1806-20 activity
  27. GRB040825A: optical observations
  28. GRB040825B: optical observations
  29. GRB040825B (=H3510): An XRF Localized in Real Time by HETE
  30. GRB 040825A: Optical observations.
  31. GRB 040812: Second epoch CXO Observations
  32. GRB040823,optical observation
  33. XRF040812: GMRT observations
  34. Triangulation of GRB 040816 (Konus-Wind - Helicon-Coronas-F)
  35. XRF040812: possible afterglow
  36. CXO observation of GRB 040812
  37. IPN/HETE localizations of GRB040810 (=H3489)
  38. GRB 040812: Keck and LCO optical observations
  39. GRB 040812: Keck and LCO observations
  40. Konus-Wind observation of GRB040810 (=H3489)
  41. GRB 040812: a long GRB detected by INTEGRAL
  42. GRB 040730: Optical observations
  43. Ongoing activity of SGR 1806-20
  44. GRB040624: optical monitoring at TNG
  45. XRF 040701 - optical observations of the decaying Chandra source
  46. Cancellation of IBAS/INTEGRAL GRB alerts
  47. XRF040701: First-Epoch Chandra Observations
  48. GRB040624, optical observations
  49. GRB040706:observation at University of Miyazaki
  50. XRF 040701, optical observations
  51. XRF040701 (=U11548): a bright XRF detected by HETE
  52. Optical Observations of GRB040624
  53. MASTER: GRB 040624 optical observation after 0,48d
  54. GRB 030329: Rebrightening of hyperluminal ejecta.
  55. IPN Summary of SGR1806-20 Activity in 2004
  56. MASTER:HETE Alert 3259 (SRG1806-20) optical observation
  57. SGR 1806-20, potential NIR counterpart
  58. GRB 040606: Optical observations
  59. Activivty of SGR 1806-20
  60. GRB 040511, very fast decay?
  61. GRB 030324: Detection and Color of Host Galaxy
  62. GRB 040511: NIR observations with REM
  63. GRB040511: Candidate optical/NIR afterglow
  64. IBAS GRB Alerts n.1785 to 1791
  65. GRB 040511: ROTSE-III Rapid Optical Upper Limits
  66. GRB 040511: Second Epoch Optical Observations
  67. GRB040511: Optical Observations
  68. GRB040511: Optical Observations
  69. GRB040511 (=H3218): A Long GRB Localized by HETE WXM and SXC
  70. Type Ic SN2001em (off-axis GRB jet?), optical spectrum
  71. GRB and XRF on April 27, 2004. Detection by Konus-Wind and Helicon (Coronas-F)
  72. On Line Availability of Archival HETE Fregate Data and Lightcurves
  73. GRB 040423 (=H3175): A Long GRB Localized by HETE
  74. GRB040422, optical observations at Loiano
  75. GRB040422 : I-band follow-up observation at Lulin Observatory
  76. GRB 040422: ROTSE-IIIb Prompt Optical Limits
  77. GRB 040422,optical observation
  78. GRB 040403, deep optical observations
  79. INTEGRAL-SPI/ACS GRB data: timing correction
  80. IBAS GRB alerts 1739, 1740, 1741
  81. HETE/IPN localization of GRB040403A (=H3143, a long burst) and GRB040403B(=H3144, a short/hard burst)
  82. Summary of recent bursts from SGR 1806-20 detected by INTEGRAL
  83. GRB 040329: hard burst detected by Konus-Wind and Helicon - Coronas-F
  84. IBAS GRB Alert 1694
  85. GRB040323: NIR Observations and Variable Object
  86. GRB 040319 (=H3128): An X-Ray-Rich GRB Localized by the HETE-2 WXM and SXC
  87. GRB 040323, a dark GRB ?
  88. short hard GRB 040322
  89. IBAS GRB alerts 1679, 1680, 1681
  90. GRB040223: Deep NIR NTT data re-analysis
  91. GRB 040223: XMM-Newton results
  92. GRB040223, improved XMM position
  93. GRB 031203: spectoscopic evidence for a 1998bw-like SN
  94. GRB 031203, possible supernova
  95. MASTER: RXTE GRB040308 optical observation
  96. GRB 040228 Optical observations
  97. IPN triangulation of GRB040228 (H3066, H3067)
  98. GRB 040228 (=H3066?,=H3067?): A Long GRB Localized by the HETE-2 WXM
  99. GRB031111, optical observations
  100. GRB031220: 2nd Chandra observation and X-ray afterglow candidate

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