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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"

32792 results found.

  1. GRB 040511: Optical Observations
  2. GRB040511: Optical Observations
  3. GRB040511: Optical Observations
  4. GRB040511 (=H3218): A Long GRB Localized by HETE WXM and SXC
  5. IBAS GRB Alert number 1774: NOT a real GRB
  6. Type Ic SN2001em (off-axis GRB jet?), optical spectrum
  7. IBAS Alerts 1771 and 1772: NOT a real GRB
  8. GRB and XRF on April 27, 2004. Detection by Konus-Wind and Helicon (Coronas-F)
  9. IPN triangulation of GRB040425 (=H3183)
  10. On Line Availability of Archival HETE Fregate Data and Lightcurves
  11. GRB040422: optical observations at CrAO
  12. GRB 040423 (=H3175): A Long GRB Localized by HETE
  13. GRB 040422: ROTSE-IIIb Prompt Optical Limits
  14. GRB040422, BVRcIc field calibration
  15. GRB 040422,optical observation
  16. GRB 040422: a long GRB detected with INTEGRAL
  17. GRB 040403, deep optical observations
  18. INTEGRAL-SPI/ACS GRB data: timing correction
  19. IBAS GRB alerts 1739, 1740, 1741
  20. HETE/IPN localization of GRB040403A (=H3143, a long burst) and GRB040403B(=H3144, a short/hard burst)
  21. GRB 040403: Optical Observations
  22. GRB 040403 Optical Observations
  23. GRB 040403: Optical observations
  24. GRB 040403: optical observations
  25. GRB 040403: Optical Observations
  26. GRB 040403: a long GRB detected with INTEGRAL
  27. GRB 040329: hard burst detected by Konus-Wind and Helicon - Coronas-F
  28. IBAS GRB Alert 1694
  29. GRB 040319 (=H3128): An X-Ray-Rich GRB Localized by the HETE-2 WXM and SXC
  30. GRB 040323, a dark GRB ?
  31. short hard GRB 040322
  32. GRB 040323: a long GRB detected with INTEGRAL
  33. IBAS GRB alerts 1679, 1680, 1681
  34. GRB040223: Deep NIR NTT data re-analysis
  35. GRB 040223: XMM-Newton results
  36. GRB040223, improved XMM position
  37. IBAS Alert 1678: not a GRB
  38. GRB 031203: spectoscopic evidence for a 1998bw-like SN
  39. GRB 031203, possible supernova
  40. GRB 040228 Optical observations
  41. IPN triangulation of GRB040228 (H3066, H3067)
  42. GRB040228 : KISO optical follow-up observation
  43. GRB 040228 (=H3066?,=H3067?): A Long GRB Localized by the HETE-2 WXM
  44. GRB 040223: Deep NIR NTT observations
  45. GRB 040223 : Optical observation (non-detection)
  46. XMM-Newton Images of GRB 040223
  47. GRB 040223, VLA observations
  48. GRB 040223: REM IJK Observations
  49. GRB 040223 XMM-Newton observation ...
  50. GRB 031203 XMM-Newton observation
  51. GRB 040223 : Planned XMM-Newton observation
  52. GRB 040106 : Planned XMM-Newton observation
  53. GRB 040223: further offline analysis
  54. GRB 040223: a long GRB detected with INTEGRAL
  55. Follow-up on IBAS GRB Alert 1379
  56. IBAS GRB alert 1379
  57. SN 2003dh/GRB030329 late-time optical spectroscopy
  58. GRB040106, likely optical afterglow
  59. GRB040106: Second Epoch Optical Observations
  60. GRB 031220: Optical observations of Chandra X-ray sources
  61. XMM-Newton Images of GRB 040106
  62. GRB040106: optical observations with REM+ROSS
  63. GRB031220: observation at Univercity of Miyazaki
  64. GRB 040106: Optical observations
  65. GRB 040106 : Planned XMM-Newton observation
  66. GRB 040106 : peak flux
  67. GRB 040106 : a long GRB detected with INTEGRAL
  68. IPN triangulation of an intermediate burst from SGR1806-20
  69. GRB031220(=H2976): TNG R-band Observation of the Chandra X-ray Sources
  70. GRB031225a triangulation (annulus)
  71. IPN triangulation of GRB031219 (large error box)
  72. GRB031220: Palomar Observations
  73. GRB 031220 : Kyoto Optical Observation
  74. GRB 031220: Subaru observation
  75. GRB 031220: Optical observation at Tokyo Tech
  76. GRB031220 : Optical Observation of Lulin Observatory
  77. GRB 031203 I-band monitoring
  78. IPN triangulation of GRB031214 (short/hard; very intense; small error box)
  79. GRB 2974 follow-up observations
  80. GRB 031203: Discovery of a dust echo
  81. GRB031214 triangulation (annulus), [repost of GCN2487, subject corrected]
  82. GRB030921 triangulation (annulus)
  83. GRB 031203: SMARTS optical monitoring
  84. GRB 021203: A Normal GRB viewed far off axis?
  85. GRB 031203: Variable Radio Source
  86. GRB 031203: Magellan spectrum of possible GRB host
  87. GRB 031203: Optical/IR Astrometry
  88. IPN/HETE localization of GRB031203B (=H2949; large error box)
  89. GRB031203: ROSAT upper limits suggest XMM-S1 source as the transient
  90. GRB 031203: Deep NIR NTT & VLT observations
  91. GRB031203: K' Photometry of the likely GRB host
  92. GRB 031203: Radio detection
  93. GRB 031203: Further reports on December 4 observations
  94. GRB 031203: IR NTTobservations do not confirm REM detection
  95. GRB031203 : Optical Observation of Lulin Observatory
  96. GRB 031203: z ~ 10 or Fragmented Dust in the Circumburst Environment?
  97. GRB 031203: Apparent Spectral Break
  98. GRB 031203: IR REM Observations
  99. GRB031203: Optical Observations
  100. GRB 031203 XMM-Newton observation

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