Skip to main content
New! BOOM Notices and Schema v7.0.0. See news and announcements

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"

41643 results found.

  1. GRB070208: optical observations
  2. GRB 070201: IPN constraints and nearby galaxies
  3. GRB 070201: Proximity of IPN annulus to M31
  4. GRB 070208: MARGE Optical Observations
  5. IPN localization of very bright long hard GRB 070207
  6. IPN localization of very intense short GRB 070201
  7. GRB 070209: Swift detection of a short hard burst
  8. GRB 070208: Swift XRT refined analysis
  9. GRB 070208: RAPTOR detection of early afterglow onset
  10. GRB070208: Absorption and emission redshift from Gemini
  11. GRB 070208: MDM Optical Decay
  12. GRB 070208, Swift-BAT refined analysis
  13. GRB070208 - SDSS Pre-Burst Observations
  14. GRB 070208: Early IR detection and afterglow astrometry
  15. GRB 070208: Afterglow confirmation from P60
  16. GRB 070208: ROTSE-III Optical Limits
  17. GRB 070208: MDM Observations
  18. GRB 070208: Swift detection of a burst
  19. GRB 070125 detection with CARMA
  20. GRB 070125: Redshift z>~1.54 from Gemini Afterglow Spectrum
  21. GRB 070129: afterglow confirmation
  22. GRB070124: Swift-XRT Follow-up Observation
  23. GRB070126: Swift-XRT Observation
  24. GRB 070125: further AAVSO optical observations
  25. GRB 070129: Swift/UVOT Upper limits
  26. GRB 070129: dust-scattered X-ray halo detected by Swift/XRT
  27. GRB 070125: optical observation
  28. GRB 070125: WSRT Radio Detection
  29. GRB070129: MITSuME optical observation
  30. Radio detection of GRB 070125
  31. GRB061217: MAGIC telescope GeV observation
  32. GRB 070125: confirmation of pseudo-redshift
  33. GRB 070129: Xinglong TNT optical Upper Limit
  34. GRB 070129: Swift-XRT Refined Analysis
  35. GRB 070129: VLT observations
  36. GRB 070125: An IR Point Source and an Apparent Host Galaxy
  37. GRB 070129: Swift detection of a burst
  38. GRB 070126: Swift/UVOT refined analysis
  39. GRB 070125: further AAVSO optical observations
  40. GRB 070125: MITSuME Okayama optical observation
  41. Konus-Wind observation of GRB 070125
  42. GRB 070125: AAVSO optical observations
  43. GRB 070125: optical observations
  44. GRB 070126: VLT observations
  45. GRB070126: Swift-XRT possible detection of an afterglow
  46. GRB 070125: PROMPT detections
  47. GRB 070124: Suzaku WAM observation of the prompt emissions
  48. GRB 070125: WSRT Radio Observations
  49. GRB 070125: UVOT Detection in Ultraviolet Filters
  50. GRB 070126, Swift-BAT refined analysis of a very faint burst
  51. GRB070125: Optical observation by Kanata
  52. GRB070124: Swift-XRT Observation
  53. Possible GRB 070126: Swift/UVOT Upper Limit
  54. GRB 070125: UVOT Observations of a Fading Optical Afterglow
  55. GRB 070125: Xinglong TNT optical observations
  56. GRB 070125: Continued P60 Observations
  57. GRB 070125: pseudo-z~1.5 from spectral parameters of the prompt emission
  58. GRB 070125: Keck/LRIS Spectroscopy -- Evidence for a very low redshift
  59. GRB 070125: Lick 3m Spectroscopy
  60. GRB070125: Swift-XRT Refined Analysis
  61. GRB 070125: SARA detection in R
  62. GRB 070125: P60 Optical Afterglow Candidate
  63. GRB 070126?: Swift detection of a possible burst
  64. RHESSI Spectrum of GRB070125
  65. IPN-BAT localization of GRB070125 (very long duration, intense)
  66. Konus-Wind observation of short hard GRB 070124
  67. IPN localization of GRB070124 (short duration, hard spectrum)
  68. GRB 070110: optical break
  69. Swift-BAT trigger 257213 is a Galactic Center transient
  70. GRB 070110: Continued Detection and Request for Ground Followup
  71. GRB 050904: Second Epoch of HST/NICMOS Observations
  72. GRB 070110: Ep,i - Eiso correlation
  73. GRB 070107: Suzaku WAM observation of the prompt emission
  74. GRB 070110: VLT R-band photometry
  75. GRB 070110 declared a "Burst of Interest" by Swift team
  76. Further Retractions of previous Swift-BAT triggers
  77. Trigger 255685: Swift detection of a possible burst
  78. GRB 070110: VLT absorption redshift
  79. GRB 070110: UVOT Observations of a Candidate Afterglow
  80. GRB070110: Swift XRT Team refined analysis
  81. GRB 070110, Swift-BAT refined analysis
  82. GRB070107 Swift/UVOT Observations of a Fading Optical Afterglow
  83. GRB 070110: Swift detection of a burst with a possible optical afterglow
  84. IBAS Alert n. 4047: Not a GRB
  85. GRB070107: Swift/XRT refined analysis
  86. GRB 070107: Possible UVOT Afterglow
  87. GRB 070107, Swift-BAT refined analysis
  88. GRB 070107: Swift/XRT position
  89. GRB 070107: Swift detection of a burst
  90. VLA observation of GRB 061222B
  91. VLA detection of GRB 061222A
  92. GRB070103: APO SPIcam i' and z' limits
  93. GRB 061201: Nearby Galaxy Cluster Abell 995 is at z=0.0865
  94. GRB070103: KPNO 4m+FLAMINGOS J limit
  95. GRB 070103: Swift/UVOT Upper limits
  96. GRB070103: Swift XRT refined analysis
  97. GRB 070103, Swift-BAT refined analysis
  98. GRB 070103: NOT observations
  99. GRB 070103: TAROT Calern observatory optical observations
  100. GRB 070103: Swift detection of a burst

Advanced

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