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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.

Advanced Search Examples (click to copy):

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

44287 results found.

  1. GRB 070306: ART-3 early optical and near infrared constraints
  2. GRB 070306: IR observations and candidate afterglow
  3. GRB 070306, Swift-BAT refined analysis
  4. GRB 070306: XRT Team Refined Analysis
  5. GRB 070306: Optical and IR observations with KANATA
  6. GRB070306 - SDSS Pre-burst Observations
  7. GRB 070306: Swift detection of a burst
  8. GRB 070223: NIR observations at WHT
  9. GRB070227: Swift-XRT refined analysis
  10. GRB 060605 new redshift
  11. GRB 070125, deep late-time optical observation
  12. VLA observation of GRB 070224
  13. GRB 070227: optical observations
  14. GRB 070223: Optical Observations
  15. GRB 070227: optical observations
  16. GRB 070227: Swift/UVOT Upper Limits
  17. GRB 070227: TAROT La Silla observatory optical observations
  18. GRB 070227, Swift-BAT refined analysis
  19. GRB070227: possible X-ray afterglow detection
  20. GRB 070227: Swift detection of a burst in ground analysis
  21. GRB 920925C: optical afterglow candidate
  22. GRB 070224: Optical afterglow confirmation
  23. IBAS Alert n. 4144: not a GRB
  24. GRB 070224: Swift/UVOT Upper Limits
  25. GRB070224: Swift-XRT Astrometrically Corrected Position
  26. VLA observation of GRB 070223
  27. VLA observation of GRB 070220
  28. GRB070224: Magellan Imaging Observations
  29. GRB 070224: WHT K-band imaging
  30. GRB 070224: MDM Observations
  31. GRB070224: Gemini Imaging Observations
  32. GRB 070224: SARA upper limit
  33. GRB070224: Swift-XRT Refined Analysis
  34. GRB 070224: optical afterglow candidate
  35. GRB 070224, Swift-BAT refined analysis
  36. GRB 070224: MASTER-Net refind analysis
  37. GRB 070224: MASTER-VWF-Kislovodsk observations
  38. GRB 070224: Swift detection of a burst
  39. GRB 070223: Optical observations
  40. RHESSI Spectrum of GRB070220
  41. GRB070223: Swift/UVOT refined analysis
  42. GRB 070223: Optical-IR observation with KANATA
  43. GRB 070223, Swift-BAT refined analysis
  44. GRB070223: MASTER-VWF-Kislovodsk observations
  45. GRB 070223: Swift-XRT Refined Analysis
  46. GRB 070220: pseudo-z~2.15 from spectral parameters of the prompt
  47. GRB070223 - SDSS Pre-Burst Observations
  48. GRB 070223: Liverpool Telescope Possible Afterglow Candidate
  49. GRB 070223: MDM Observations
  50. GRB070223: Swift burst
  51. Konus-Wind and Konus-A observations of GRB 070220
  52. GRB 070220: MITSuME Okayama Optical Observation
  53. GRB 070220: ART-3 Optical and NIR limits
  54. GRB 070220 Swift-BAT Refined Analysis
  55. Swift/UVOT refined analysis of GRB070220
  56. GRB 070209: Swift XRT refined analysis
  57. GRB 070220: Swift-XRT Refined Analysis
  58. GRB 070220: Observation with the KANATA 1.5m telescope
  59. GRB 070219: Gemini Observations
  60. GRB 070220 : Faulkes Telescope North optical limit
  61. GRB 070220: Swift detection of a burst
  62. GRB070219: MASTER-VWF-Kislovodsk observations
  63. GRB 070219: XRT Refined Analysis
  64. GRB 070219: Swift/UVOT Upper limits
  65. GRB 070219: I-band observations
  66. GRB 070219, Swift-BAT refined analysis
  67. GRB 070219: optical TNG observations
  68. GRB 070219: Liverpool Telescope Observations
  69. GRB 070219: ROTSE-III Optical Limits
  70. GRB070219 - SDSS Pre-Burst Observations
  71. GRB 070219: Swift detection of a burst
  72. IPN triangulation of GRB070201 (refined error box using MESSENGER data)
  73. GRB 070125 observations with the GMRT
  74. GRB 070209: Redshift of a galaxy in the error circle of XRT source
  75. Swift-BAT trigger 260304 is NOT a burst or transient
  76. GRB 060927: PROMPT Observations
  77. GRB 070201: Correction to GCN 6094
  78. GRB 070129: MDM I-band Detection
  79. GRB 070125: Break in Optical Decay
  80. GRB 070209: Swift XRT analysis
  81. GRB 070201: clarification on localization and Konus-Wind spectra
  82. GRB070208: optical observations
  83. GRB 070201: IPN constraints and nearby galaxies
  84. GRB 070201: Proximity of IPN annulus to M31
  85. GRB 070208: MARGE Optical Observations
  86. IPN localization of very bright long hard GRB 070207
  87. IPN localization of very intense short GRB 070201
  88. GRB 070209, Swift-BAT refined analysis of the short hard burst
  89. GRB 070209: Swift detection of a short hard burst
  90. GRB 070208: Swift XRT refined analysis
  91. GRB 070208: RAPTOR detection of early afterglow onset
  92. GRB070208: Absorption and emission redshift from Gemini
  93. GRB 070208: MDM Optical Decay
  94. GRB 070208, Swift-BAT refined analysis
  95. GRB070208 - SDSS Pre-Burst Observations
  96. GRB 070208: Early IR detection and afterglow astrometry
  97. GRB 070208: Afterglow confirmation from P60
  98. GRB070208: Faulkes Telescope North Afterglow Identification
  99. GRB 070208: ROTSE-III Optical Limits
  100. GRB 070208: MDM Observations

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