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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"

26500 results found.

  1. GRB040422 : I-band follow-up observation at Lulin Observatory
  2. GRB 040422: ROTSE-IIIb Prompt Optical Limits
  3. GRB040422, BVRcIc field calibration
  4. GRB 040422,optical observation
  5. GRB040422: optical and NIR observations at the VLT
  6. GRB 040403, deep optical observations
  7. MASTER: HETE Alert 3163, 3167 technical optical observation
  8. INTEGRAL-SPI/ACS GRB data: timing correction
  9. HETE/IPN localization of GRB040403A (=H3143, a long burst) and GRB040403B(=H3144, a short/hard burst)
  10. GRB 040403 Optical Observations
  11. GRB 040403: Optical observations
  12. GRB 040403: optical observations
  13. Summary of recent bursts from SGR 1806-20 detected by INTEGRAL
  14. GRB040323: NIR Observations and Variable Object
  15. GRB 040319 (=H3128): An X-Ray-Rich GRB Localized by the HETE-2 WXM and SXC
  16. GRB 040323, a dark GRB ?
  17. GRB 040323: a long GRB detected with INTEGRAL
  18. GRB 040223: XMM-Newton results
  19. GRB040223, improved XMM position
  20. GRB 031203, possible supernova
  21. MASTER: RXTE GRB040308 optical observation
  22. IBAS results on a burst from SGR1806-20
  23. RXTE GRB040229 optical observation: no candidate
  24. GRB040228 : KISO optical follow-up observation
  25. GRB 040228 (=H3066?,=H3067?): A Long GRB Localized by the HETE-2 WXM
  26. GRB 040223: Deep NIR NTT observations
  27. GRB 040223 : Optical observation (non-detection)
  28. XMM-Newton Images of GRB 040223
  29. GRB 040223, VLA observations
  30. GRB 040223: REM IJK Observations
  31. GRB 040223 XMM-Newton observation ...
  32. GRB 031203 XMM-Newton observation
  33. GRB031111, optical observations
  34. GRB031220: 2nd Chandra observation and X-ray afterglow candidate
  35. GRB031203: Chandra Observations
  36. GRB040106: refined X-ray transient position
  37. GRB040106, likely optical afterglow
  38. GRB 031220: Optical observations of Chandra X-ray sources
  39. XMM-Newton Images of GRB 040106
  40. GRB031220: observation at Univercity of Miyazaki
  41. XMM-Newton observation of GRB040106
  42. GRB 040106 : peak flux
  43. GRB031220(=H2976): TNG R-band Observation of the Chandra X-ray Sources
  44. GRB031220(=H2976): Observation with the Chandra X-ray Observatory
  45. GRB031220: Palomar Observations
  46. GRB 031220 : Kyoto Optical Observation
  47. GRB 031220: Subaru observation
  48. GRB 031220: Optical observation at Tokyo Tech
  49. GRB031220: ROTSE-IIIb Optical Limits
  50. GRB 2974 follow-up observations
  51. GRB031203, improved XMM position
  52. GRB 031203: SMARTS optical monitoring
  53. GRB 021203: A Normal GRB viewed far off axis?
  54. XMM-Newton Observations of GRB031203: Preliminary Images
  55. GRB031203: ROSAT upper limits suggest XMM-S1 source as the transient
  56. XMM-Newton Observation of GRB031203
  57. GRB031203: K' Photometry of the likely GRB host
  58. XMM-Newton Observation of GRB031203
  59. GRB 031203: Radio detection
  60. GRB 031203: IR NTTobservations do not confirm REM detection
  61. GRB 031203: z ~ 10 or Fragmented Dust in the Circumburst Environment?
  62. GRB031203: Planned XMM-Newton observation II
  63. GRB 031203: IR REM Observations
  64. GRB031203: Optical Observations
  65. GRB 031203 XMM-Newton observation
  66. GRB031203: Planned XMM-Newton observation
  67. GRB 031203: further analysis of INTEGRAL data
  68. GRB 030329: Planned XMM-Newton Observation
  69. GRB 031111B (= H2925) : Kyoto Optical Observation
  70. IPN triangulation of GRB031114 (large error box)
  71. GRB 031111: Optical observations
  72. GRB 031111, optical observations
  73. SN 2003jd (SN/GRB?) -- X-ray Observations
  74. XRF031109 (=H2919): A very long XRF localized by HETE
  75. IPN triangulation of GRB031108 (large error box)
  76. GRB031026: 1.2mm upper limit with MAMBO at the IRAM 30m
  77. GRB030929/SN2003jd association unlikely based on IPN localiztion
  78. IPN triangulation of GRB031027 (small error box)
  79. Lulin optical follow-up observations of GRB031026
  80. IPN triangulation of GRB031024 (single error box)
  81. GRB031026 (=H2882): A Long, Hard Spectrum Burst Localized by HETE
  82. GRB031026 : KISO optical follow-up observation
  83. IPN triangulation of GRB031024 (annulus)
  84. IPN triangulation of GRB031020 (large error box)
  85. GRB030329: radio observations at RT-22 (CrAO)
  86. Ongoing Bursting Activity from SGR 1806-20 detected with IBAS
  87. XRF 030824: additional observations at CFHT
  88. SGR 1806-20 bursts with INTEGRAL and IBAS announcement on Soft Gamma-Ray Repeaters
  89. XRF 030723: Subaru Optical Observations
  90. A burst from SGR 1806-20 detected with IBAS
  91. XRF 030824: Early follow-up observation at Kiso observatory
  92. XRF 030824: observations at CFHT
  93. IPN triangulation of GRB030922B (large error box)
  94. XRF 030723: Detection of the likely host galaxy
  95. XRF030824 (=H2821): An X-Ray Flash Localized by the HETE WXM
  96. XRF030823 (=H2818): An X-Ray Flash Localized by the HETE WXM and SXC
  97. IPN triangulation of GRB030921 (large error box)
  98. IPN triangulation of GRB030919 (large error box)
  99. GRB030913: Subaru Optical Observations
  100. GRB 030913: ROTSE-3c Optical Observations

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