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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"

37103 results found.

  1. GRB020410, optical observations
  2. BeppoSAX ALERT: possible GRB020410
  3. X-ray afterglow of GRB020321
  4. BeppoSAX GRB : GRB020409
  5. GRB020331: Confirmation of Afterglow Candidate with Magellan
  6. GRB020405: VLT optical observations and V band decay slope
  7. GRB020331 optical observations with RIMOTS
  8. GRB020124 optical observations with RIBOTS/RIMOTS
  9. GRB 020321: Candidate X-ray Counterparts
  10. ASM GRB candidate 020406 refined error box
  11. GRB 020405: Moderate-resolution spectroscopy
  12. GRB020406(?), optical observations
  13. GRB020405: VLT optical observations
  14. Revised Photometry of the Optical Afterglow of GRB 020405
  15. GRB020405: OT observations
  16. GRB 020331: Candidate Optical Afterglow
  17. GRB 020405: Decay index
  18. Short RXTE/ASM transient 020406; may be a GRB
  19. GRB020405, Radio Observations
  20. Fading Optical Afterglow and Possible Host Galaxy of GRB 020405
  21. GRB 020405, U-band observations
  22. GRB 020405: Optical afterglow candidate
  23. IPN localization of GRB020405
  24. GRB011212: Optical Observations
  25. GRB 020331: NIR Observations
  26. GRB 020331: NIR Observations
  27. GRB020331 NIR observation at KPNO (re-submission)
  28. GRB02033 NIR observation at KPNO
  29. GRB020331 field photometry
  30. GRB 020331 Optical Observations
  31. GRB 020331, NIR observations
  32. GRB 020331: Optical observations
  33. GRB020331(=H1963): The "Easter" Burst Detected by HETE
  34. GRB 020321: Infrared observations
  35. GRB 020322: BeppoSAX observations of the X-ray afterglow
  36. SN 2002ap - peak brightness date (SN/GRB?)
  37. GRB 020322, Radio observations
  38. Near-Infrared Observations of GRB020322 at TIRGO
  39. GRB 020321, Radio Observations
  40. GRB 020322: Optical Observations
  41. GRB020127: Proposed Host Galaxy Detection and Identification of Afterglow
  42. GRB 020321: Optical observations
  43. GRB020317 BVRI field photometry
  44. GRB011211 revised BVRI field photometry
  45. GRB020305 BVRI field photometry
  46. GRB020322 BVRI field photometry
  47. GRB 020322 optical observations
  48. GRB 020322 optical observation
  49. GRB020317 : Near IR Observations from Mt Abu Observatory
  50. GRB 020322: Optical Sources and Improved Astrometry
  51. GRB020322, optical observations
  52. GRB 020322: Optical candidate
  53. GRB020322: Optical Observations
  54. GRB020322: BeppoSAX/NFI Observations
  55. Bepposax GRB020322 The second springtime BSAX GRB
  56. GRB 020321: Optical observations
  57. GRB 011121: Fourth Epoch of HST Imaging
  58. GRB020317: optical observations
  59. GRB020321 optical observations
  60. GRB020321: BeppoSAX/NFI Observations
  61. GRB020321: a faint BeppoSAX detection
  62. GRB 020317 : KISO Optical Observations
  63. BeppoSAX ALERT: GRB020321, the "Springtime Burst"
  64. GRB020317 (=H1959): Localization by HETE of a Low Fluence GRB
  65. GRB 020305: Optical Observations
  66. GRB020317, optical observations
  67. GRB 020317: Optical observations
  68. GRB 011121: Third HST Epoch
  69. GRB020305: Properties of the Candidate Optical Afterglow
  70. GRB 011121: HST Observations reveal an intermediate-time multicolor
  71. GRB011121, possible supernova association
  72. GRB011130 (XRF011130) Second Epoch Chandra Observations
  73. GRB020305: Subaru Optical Observations
  74. GRB 020305: Optical observations
  75. XRF/GRB 011030 Images
  76. XRF/GRB 011030: Detection of the Probable Host Galaxy
  77. GRB 020305: Candidate optical afterglow
  78. Type Ic SN2002bl (SN/GRB?) Radio Observations
  79. GRB020305: Optical Observations
  80. IPN triangulation of GRB020305 (HETE 1939)
  81. GRB020305 (=H1939): Localization of a GRB by HETE
  82. GRB 020305: Optical observations
  83. HST Imaging of the afterglow and host of GRB 011121
  84. GRB 010921: HST Observations
  85. IPN detection and localization of Cygnus X-1 flares
  86. GRB020127: Further VLA Observations of Possible Counterparts
  87. IPN detection of further SGR1900+14 activity
  88. SGR1900+14 activity
  89. IPN/HETE Detection of Bursts from SGR1900+14
  90. IPN Upper Limits to a GRB Associated With SN2002ap
  91. GRB020124 BVRI field photometry
  92. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  93. SN2002ap (SN/GRB?) Echelle spectra
  94. SN2002ap (SN/GRB?) optical spectrographic observations
  95. GRB020127 Optical Observations
  96. SN 2002ap (SN/GRB?)
  97. SN2002ap (SN/GRB?) UBVRI Field Photometry
  98. GRB020127: Chandra Observations and Prospective Counterparts
  99. pre-SN2002ap (SN/GRB?) imaging of M74
  100. SN 2002ap (hypernova / GRB ??): special list on VSNET

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