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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').
Advanced Search

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"

32504 results found.

  1. GRB040223, improved XMM position
  2. GRB 031203: spectoscopic evidence for a 1998bw-like SN
  3. GRB 031203, possible supernova
  4. IBAS results on a burst from SGR1806-20
  5. GRB 040228 Optical observations
  6. IPN triangulation of GRB040228 (H3066, H3067)
  7. GRB 040228 (=H3066?,=H3067?): A Long GRB Localized by the HETE-2 WXM
  8. GRB 040223: Deep NIR NTT observations
  9. GRB 040223 : Optical observation (non-detection)
  10. XMM-Newton Images of GRB 040223
  11. GRB 040223, VLA observations
  12. GRB 040223: REM IJK Observations
  13. GRB 040223 XMM-Newton observation ...
  14. GRB 031203 XMM-Newton observation
  15. GRB031111, optical observations
  16. GRB031220: 2nd Chandra observation and X-ray afterglow candidate
  17. GRB031203: Chandra Observations
  18. GRB040106, follow-up radio observations
  19. GRB040106: refined X-ray transient position
  20. Follow-up on IBAS GRB Alert 1379
  21. SN 2003dh/GRB030329 late-time optical spectroscopy
  22. GRB040106, Radio Observations
  23. GRB040106, likely optical afterglow
  24. GRB040106: Second Epoch Optical Observations
  25. GRB 031220: Optical observations of Chandra X-ray sources
  26. XMM-Newton Images of GRB 040106
  27. GRB040106: optical observations with REM+ROSS
  28. GRB031220: observation at Univercity of Miyazaki
  29. GRB 040106: Optical observations
  30. XMM-Newton observation of GRB040106
  31. GRB031220(=H2976): TNG R-band Observation of the Chandra X-ray Sources
  32. GRB031220(=H2976): Observation with the Chandra X-ray Observatory
  33. GRB 031203 I-band monitoring
  34. IPN triangulation of GRB031214 (short/hard; very intense; small error box)
  35. GRB 2974 follow-up observations
  36. GRB031203, improved XMM position
  37. GRB 031203: SMARTS optical monitoring
  38. GRB 021203: A Normal GRB viewed far off axis?
  39. GRB 031203: Variable Radio Source
  40. GRB 031203: Magellan spectrum of possible GRB host
  41. GRB 031203: Optical/IR Astrometry
  42. GRB031203 K prime photometry: correction to galaxy coordinates
  43. GRB031203: ROSAT upper limits suggest XMM-S1 source as the transient
  44. XMM-Newton Observation of GRB031203
  45. GRB031203: K' Photometry of the likely GRB host
  46. XMM-Newton Observation of GRB031203
  47. GRB 031203: Radio detection
  48. GRB 031203: Further reports on December 4 observations
  49. GRB 031203: IR NTTobservations do not confirm REM detection
  50. GRB 031203: z ~ 10 or Fragmented Dust in the Circumburst Environment?
  51. GRB 031203: Apparent Spectral Break
  52. GRB031203: Planned XMM-Newton observation II
  53. GRB 031203: IR REM Observations
  54. GRB031203: Optical Observations
  55. GRB 031203 XMM-Newton observation
  56. GRB 031203: Optical/IR SMARTS Observations
  57. GRB031203: Planned XMM-Newton observation
  58. GRB031111A, prompt optical observations
  59. GRB 031111, Radio observations
  60. GRB 031111: Optical observations
  61. GRB 031111, optical observations
  62. SN 2003jd (SN/GRB?) -- X-ray Observations
  63. IPN triangulation of GRB031111 (=H2924): small error box
  64. XRF031109 (=H2919): A very long XRF localized by HETE
  65. GRB031026: 1.2mm upper limit with MAMBO at the IRAM 30m
  66. GRB030929/SN2003jd association unlikely based on IPN localiztion
  67. Lulin optical follow-up observations of GRB031026
  68. SN 2003jd (SN/GRB?), Radio Observations
  69. SN 2003jd (SN/GRB?) - possible association with GRB 030929
  70. GRB 031026: Further Ic Observations
  71. GRB 031026 (=H2882): Evidence for High Redshift from Prompt
  72. Peculiar Type Ic SN 2003jd (SN/GRB?), optical spectrum
  73. IPN triangulation of GRB031024 (single error box)
  74. GRB031026 (=H2882): A Long, Hard Spectrum Burst Localized by HETE
  75. XRF 030824: additional observations at CFHT
  76. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  77. SGR 1806-20 bursts with INTEGRAL and IBAS announcement on Soft Gamma-Ray Repeaters
  78. XRF 030723: Subaru Optical Observations
  79. XRF 030824: Early follow-up observation at Kiso observatory
  80. XRF 030723: Detection of the likely host galaxy
  81. XRF030824 (=H2821): An X-Ray Flash Localized by the HETE WXM
  82. XRF030823 (=H2818): An X-Ray Flash Localized by the HETE WXM and SXC
  83. IPN triangulation of GRB030922A (large error box)
  84. IPN triangulation of GRB030921 (large error box)
  85. GRB030913: Subaru Optical Observations
  86. GRB 030913: ROTSE-3c Optical Observations
  87. GRB030913: OT's limit by MASTER
  88. GRB030913, candidate afterglow observations
  89. GRB030913: AAVSO optical observations
  90. GRB030913 (=H2849): Confirmation of the Flight Localization
  91. GRB030913 (=H2849): TAROT Observations
  92. Magellan Observations of GRB030725 (=H2779)
  93. GRB030913 (=H2849): A GRB Possibly Localized by HETE
  94. IBAS detection of bursts from SGR 1806-20
  95. Radio Observations of SGR1806-20
  96. GRB 030824: Candidate Follow-Up
  97. XRF030824: Second-epoch Palomar observations
  98. XRF030824: optical observations
  99. XRF030824: Palomar observations
  100. GRB030823: optical observation at Tokyo Tech

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