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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"

44418 results found.

  1. GRB020405: OT observations
  2. GRB 020331: Candidate Optical Afterglow
  3. GRB 020405: Decay index
  4. Short RXTE/ASM transient 020406; may be a GRB
  5. GRB020405, Radio Observations
  6. GRB020405: VLT spectroscopy
  7. Fading Optical Afterglow and Possible Host Galaxy of GRB 020405
  8. V band observations of GRB020405
  9. GRB 020405, U-band observations
  10. GRB 020405: Optical afterglow candidate
  11. IPN localization of GRB020405
  12. GRB011212: Optical Observations
  13. GRB 020331: NIR Observations
  14. GRB 020331: NIR Observations
  15. GRB020331 NIR observation at KPNO (re-submission)
  16. GRB02033 NIR observation at KPNO
  17. GRB020331 field photometry
  18. GRB 020331 Optical Observations
  19. GRB 020331, NIR observations
  20. GRB 020331: Optical observations
  21. GRB020331(=H1963): The "Easter" Burst Detected by HETE
  22. GRB 020321: Infrared observations
  23. GRB 020322: BeppoSAX observations of the X-ray afterglow
  24. SN 2002ap - peak brightness date (SN/GRB?)
  25. GRB011211: HST Observations of Optical Afterglow and Host Galaxy
  26. GRB 020322, Radio observations
  27. Near-Infrared Observations of GRB020322 at TIRGO
  28. GRB 020321, Radio Observations
  29. GRB 020322: Optical Observations
  30. GRB020127: Proposed Host Galaxy Detection and Identification of Afterglow
  31. GRB 020321: Optical observations
  32. GRB020317 BVRI field photometry
  33. GRB011211 revised BVRI field photometry
  34. GRB020305 BVRI field photometry
  35. GRB020322 BVRI field photometry
  36. GRB 020322 optical observations
  37. GRB020322: Candidate Optical Afterglow
  38. GRB 020322 optical observation
  39. GRB020317 : Near IR Observations from Mt Abu Observatory
  40. GRB 020322: Optical Sources and Improved Astrometry
  41. GRB020322, optical observations
  42. GRB 020322: Optical candidate
  43. XMM-Newton observation of GRB020322
  44. GRB020322: Optical Observations
  45. GRB020322: BeppoSAX/NFI Observations
  46. GRB 020321: Optical observations
  47. GRB 011121: Fourth Epoch of HST Imaging
  48. GRB020317: optical observations
  49. GRB020321 optical observations
  50. GRB020321: BeppoSAX/NFI Observations
  51. GRB020321: a faint BeppoSAX detection
  52. GRB020305: NIR observations
  53. GRB 020317 : KISO Optical Observations
  54. BeppoSAX ALERT: GRB020321, the "Springtime Burst"
  55. GRB020317 (=H1959): Localization by HETE of a Low Fluence GRB
  56. GRB 020305: Optical Observations
  57. GRB020317, optical observations
  58. GRB 020317: Optical observations
  59. GRB 011121: Third HST Epoch
  60. GRB020305: Properties of the Candidate Optical Afterglow
  61. GRB 011121: HST Observations reveal an intermediate-time multicolor
  62. GRB011121, possible supernova association
  63. GRB011130 (XRF011130) Second Epoch Chandra Observations
  64. GRB020305: Subaru Optical Observations
  65. GRB 020305: Optical observations
  66. XRF/GRB 011030 Images
  67. XRF/GRB 011030: Detection of the Probable Host Galaxy
  68. GRB 020305: Candidate optical afterglow
  69. Type Ic SN2002bl (SN/GRB?) Radio Observations
  70. GRB020305, optical observations
  71. GRB020305: Optical Observations
  72. IPN triangulation of GRB020305 (HETE 1939)
  73. GRB020305 (=H1939): Localization of a GRB by HETE
  74. GRB 020305: Optical observations
  75. HST Imaging of the afterglow and host of GRB 011121
  76. GRB 010921: HST Observations
  77. IPN detection and localization of Cygnus X-1 flares
  78. GRB020127: Further VLA Observations of Possible Counterparts
  79. RXTE Observations of SGR 1900+14
  80. IPN detection of further SGR1900+14 activity
  81. SGR1900+14 activity
  82. IPN/HETE Detection of Bursts from SGR1900+14
  83. IPN Upper Limits to a GRB Associated With SN2002ap
  84. GRB020124 BVRI field photometry
  85. GRB020127: Palomar and VLA Observations of Possible Counterparts
  86. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  87. SN2002ap (SN/GRB?) Echelle spectra
  88. SN2002ap (SN/GRB?) optical spectrographic observations
  89. GRB020127, WSRT radio observations
  90. GRB020127 Optical Observations
  91. SN 2002ap (SN/GRB?)
  92. SN 2002ap in M74
  93. SN2002ap (SN/GRB?) UBVRI Field Photometry
  94. GRB020127: Chandra Observations and Prospective Counterparts
  95. pre-SN2002ap (SN/GRB?) imaging of M74
  96. SN 2002ap (hypernova / GRB ??): special list on VSNET
  97. Type Ib/c SN2002ap (SN/GRB?)
  98. Type Ib/c SN2002ap (SN/GRB?) Radio Observations
  99. GRB020124, optical observations
  100. GRB020127: Optical observations

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