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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"

15687 results found.

  1. GRB 060110: Optical observation
  2. GRB 060110: Optical limit
  3. GRB060109, optical observation
  4. GRB060108: P200 Ks Observations
  5. GRB 060108: early UKIRT K-band observations
  6. GRB 060108: a dark burst?
  7. GRB 060108: Mitsume optical observations
  8. GRB060108: Faulkes Telescope observation
  9. GRB060108, optical observation
  10. GRB 060105: Mitsume optical observations
  11. GRB060105, optical observation
  12. GRB060105 : Kiso optical observation
  13. GRB051211B: optical observations
  14. GRB 051221B: Optical Observations with Kuiper 1.54m
  15. GRB 051227: optical observation
  16. GRB 051221A: VLA Radio Observations
  17. GRB051227: Radio Observations
  18. GRB 051227: optical afterglow
  19. GRB 051227: Joint Swift-HETE Spectral Analysis
  20. GRB 051227, optical observation
  21. GRB051117B: optical observation
  22. GRB 051221A: MDM Optical Observations
  23. GRB 051221A: Chandra Afterglow Position
  24. GRB 051221B: ROTSE-III Optical Limits
  25. GRB 051221B: TAROT optical limits
  26. GRB 051221A: WSRT Radio Observations
  27. GRB 051221: Continued fading of optical afterglow
  28. Possible GRB 051221B: MDM Optical Detection
  29. GRB 051221A: RAPTOR Fading Counterpart Constraint
  30. GRB 051221B: BOOTES optical observations.
  31. GRB 051211A: Evidence This Is a Short Burst from Analysis of Spectral
  32. GRB 051221: Discovery of fading optical afterglow
  33. GRB 051221: Possible nearby cluster
  34. GRB 051221: IR Observations at GRB+1hr
  35. GRB051211A (=H3979): Refined Analysis
  36. GRB 051211B: optical afterglow
  37. GRB051211A: possible optical candidate
  38. GRB051105: optical observations
  39. GRB 051211B, optical observation
  40. GRB 051211a: RTT150 optical observations
  41. GRB051211B, RBO optical observations
  42. GRB 051211A: Swift/UVOT upper limits
  43. GRB 051211A,optical observation
  44. GRB 051211B: Swift XRT confirmation of the afterglow
  45. GRB051211B: Liverpool Telescope observation
  46. GRB 051211b: RTT150 optical observations
  47. GRB 051211A and GRB051211B: BOOTES simultaneous observations
  48. GRB 051211B: Swift XRT Observations
  49. GRB 051211: TAROT optical limits
  50. GRB 051211B: a possible optical detection by TAROT
  51. GRB 051211:IAC80 optical observations
  52. HETE SXC localization of GRB 051211 (=H3979)
  53. GRB 051210: Optical imaging from Las Campanas
  54. GRB051210: Swift UVOT Observation
  55. GRB051117B: optical observation
  56. GRB051111: optical observaion
  57. GRB051117b: No Swift/UVOT Detection
  58. GRB051111: Rc optical observations: correction
  59. GRB051111: Rc optical observations
  60. GRB 051109B: GAO 150cm telescope Optical limit
  61. GRB 051109A : GAO 150cm telescope Rc-band detection
  62. GRB 051021 Optical Observations
  63. GRB 051117B: MARGE Optical Limits
  64. GRB 051117B,optical observation
  65. GRB 051117B: Optical observations
  66. GRB 051117B: ROTSE-III Optical Limits
  67. GRB 051028 Optical Observations
  68. GRB050925: analysis of the XMM-Newton observation
  69. GRB051109A optical observations
  70. GRB 051111: Radio afterglow
  71. GRB 051111: AEOS optical observations
  72. GRB051111: Swift/UVOT Observations
  73. GRB 051111A : R-band temporal decay index based on Lulin
  74. GRB051111: XRT preliminary analysis
  75. GRB 051109A Optical Observations
  76. GRB 051111A : Lulin BVRI multi band afterglow observation
  77. GRB 051111A: KAIT optical observations
  78. GRB 051111: ROTSE-III Analysis of Prompt Counterpart
  79. GRB 051109A
  80. GRB 051105a: GETS optical limit
  81. GRB 051109A: KAIT optical observations
  82. Early RAPTOR measurements of GRB 051109a - the movie.
  83. GRB 051109B: ROTSE-III Optical Limits
  84. GRB 051109A: Swift-UVOT Observations
  85. GRB 051109B : Lulin Optical Observations
  86. GRB 051109A : Lulin BVRI Optical afterglow observation
  87. GRB051109A: XRT refined analysis
  88. GRB 051109a: BOOTES R & I-band detection of the early afterglow
  89. GRB 051109B Kiso optical follow-up observation
  90. GRB051105B: REM Optical observation
  91. GRB 051109: HET Optical Spectrum and Absorption Redshift
  92. GRB 051109: Rc and Ic observations
  93. GRB 051109a: IR Photometry and Astrometry
  94. GRB 051109A: ROTSE-III Decline rate for Optical Counterpart
  95. GRB051105B: Swift/XRT upper limit
  96. GRB051103: optical observations
  97. GRB 051103, optical observations
  98. GRB051103: MASTER: OT limit and host galaxy candidates
  99. GRB051028: Swift-XRT refined analysis
  100. GRB 051105a, observation from Naini Tal and OSN

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