Skip to main content
JSON Notices via Email, Kafka Cron Jobs, Submitter Profile, GCN is Hiring. See news and announcements

GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

43900 results found.

  1. GRB 070306: IR observations and candidate afterglow
  2. GRB 070306, Swift-BAT refined analysis
  3. GRB 070306: XRT Team Refined Analysis
  4. GRB 070306: Optical and IR observations with KANATA
  5. GRB070306 - SDSS Pre-burst Observations
  6. GRB 070306: Swift detection of a burst
  7. GRB 070223: NIR observations at WHT
  8. GRB070227: Swift-XRT refined analysis
  9. GRB 060605 new redshift
  10. GRB 070125, deep late-time optical observation
  11. VLA observation of GRB 070224
  12. GRB 070227: optical observations
  13. GRB 070223: Optical Observations
  14. GRB 070227: optical observations
  15. GRB 070227: Swift/UVOT Upper Limits
  16. GRB 070227: TAROT La Silla observatory optical observations
  17. GRB 070227, Swift-BAT refined analysis
  18. GRB070227: possible X-ray afterglow detection
  19. GRB 070227: Swift detection of a burst in ground analysis
  20. GRB 920925C: optical afterglow candidate
  21. GRB 070224: Optical afterglow confirmation
  22. IBAS Alert n. 4144: not a GRB
  23. GRB 070224: Swift/UVOT Upper Limits
  24. GRB070224: Swift-XRT Astrometrically Corrected Position
  25. VLA observation of GRB 070223
  26. VLA observation of GRB 070220
  27. GRB070224: Magellan Imaging Observations
  28. GRB 070224: WHT K-band imaging
  29. GRB 070224: MDM Observations
  30. GRB070224: Gemini Imaging Observations
  31. GRB 070224: SARA upper limit
  32. GRB070224: Swift-XRT Refined Analysis
  33. GRB 070224: optical afterglow candidate
  34. GRB 070224, Swift-BAT refined analysis
  35. GRB 070224: MASTER-Net refind analysis
  36. GRB 070224: MASTER-VWF-Kislovodsk observations
  37. GRB 070224: Swift detection of a burst
  38. GRB 070223: Optical observations
  39. RHESSI Spectrum of GRB070220
  40. GRB070223: Swift/UVOT refined analysis
  41. GRB 070223: Optical-IR observation with KANATA
  42. GRB 070223, Swift-BAT refined analysis
  43. GRB070223: MASTER-VWF-Kislovodsk observations
  44. GRB 070223: Swift-XRT Refined Analysis
  45. GRB 070220: pseudo-z~2.15 from spectral parameters of the prompt
  46. GRB070223 - SDSS Pre-Burst Observations
  47. GRB 070223: Liverpool Telescope Possible Afterglow Candidate
  48. GRB 070223: MDM Observations
  49. GRB070223: Swift burst
  50. Konus-Wind and Konus-A observations of GRB 070220
  51. GRB 070220: MITSuME Okayama Optical Observation
  52. GRB 070220 Swift-BAT Refined Analysis
  53. Swift/UVOT refined analysis of GRB070220
  54. GRB 070209: Swift XRT refined analysis
  55. GRB 070220: Swift-XRT Refined Analysis
  56. GRB 070220: Observation with the KANATA 1.5m telescope
  57. GRB 070219: Gemini Observations
  58. GRB 070220 : Faulkes Telescope North optical limit
  59. GRB 070220: Swift detection of a burst
  60. GRB070219: MASTER-VWF-Kislovodsk observations
  61. GRB 070219: XRT Refined Analysis
  62. GRB 070219: Swift/UVOT Upper limits
  63. GRB 070219: I-band observations
  64. GRB 070219, Swift-BAT refined analysis
  65. GRB 070219: optical TNG observations
  66. GRB 070219: Liverpool Telescope Observations
  67. GRB 070219: ROTSE-III Optical Limits
  68. GRB070219 - SDSS Pre-Burst Observations
  69. GRB 070219: Swift detection of a burst
  70. IPN triangulation of GRB070201 (refined error box using MESSENGER data)
  71. GRB 070125 observations with the GMRT
  72. GRB 070209: Redshift of a galaxy in the error circle of XRT source
  73. Swift-BAT trigger 260304 is NOT a burst or transient
  74. GRB 060927: PROMPT Observations
  75. GRB 070129: MDM I-band Detection
  76. GRB 070125: Break in Optical Decay
  77. GRB 070209: Swift XRT analysis
  78. GRB 070201: clarification on localization and Konus-Wind spectra
  79. GRB070208: optical observations
  80. GRB 070201: IPN constraints and nearby galaxies
  81. GRB 070201: Proximity of IPN annulus to M31
  82. IPN localization of very bright long hard GRB 070207
  83. IPN localization of very intense short GRB 070201
  84. GRB 070209, Swift-BAT refined analysis of the short hard burst
  85. GRB 070209: Swift detection of a short hard burst
  86. GRB 070208: Swift XRT refined analysis
  87. GRB 070208: RAPTOR detection of early afterglow onset
  88. GRB070208: Absorption and emission redshift from Gemini
  89. GRB 070208: MDM Optical Decay
  90. GRB 070208, Swift-BAT refined analysis
  91. GRB070208 - SDSS Pre-Burst Observations
  92. GRB 070208: Early IR detection and afterglow astrometry
  93. GRB 070208: Afterglow confirmation from P60
  94. GRB070208: Faulkes Telescope North Afterglow Identification
  95. GRB 070208: ROTSE-III Optical Limits
  96. GRB 070208: Swift detection of a burst
  97. GRB 070125 detection with CARMA
  98. Swift-BAT trigger 259527 is a Cosmic Ray Shower
  99. GRB 070125: Redshift z>~1.54 from Gemini Afterglow Spectrum
  100. GRB 070129: afterglow confirmation

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Looking for U.S. government information and services? Visit USA.gov