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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"

24767 results found.

  1. HST Imaging of the Host of GRB 011121
  2. GRB020801, optical afterglow candidate
  3. GRB020331: Late-time Optical Light Curve (re-submission)
  4. GRB020331: Late-time Optical Light Curve
  5. IPN triangulation of GRB020714
  6. IPN triangulation of GRB020715 (=GRB150702)
  7. IPN triangulation of GRB020714
  8. IPN triangulation of GRB150702
  9. GRB 020410: Discovery of Probable OT by HST
  10. GRB 020124, HST observations of the fading afterglow
  11. IPN triangulation of GRB020708
  12. IPN triangulation of GRB020708
  13. Correction to IPN error box for GRB020706
  14. IPN triangulation of GRB020706
  15. GRB 020705: Optical observations
  16. GRB 020625, optical observations
  17. GRB 020625: Optical observations
  18. GRB 020531: optical photometry of Chandra sources
  19. GRB020625 (=H2081): A Long Burst Localized by HETE
  20. The Probable Host Galaxy of GRB/XRF 020427
  21. GRB/XRF 020427, detection of an underlying system with the VLT
  22. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  23. AXP 1E2259+586 optical observations
  24. Fading Optical Source in the Field of GRB020531
  25. GRB 020531, INT+WFC deep optical upper limits
  26. SGR-like Bursts from the AXP 1E 2259+586
  27. GRB020405: polarimetric observations
  28. GRB 020531, simultaneous optical observations
  29. GRB 020531/Candidate Redshift
  30. GRB020531: Detection of Candidate Host Galaxy
  31. GRB020531: Second epoch Chandra observations
  32. GRB020604, optical observations
  33. GRB020604, BVRcIc field photometry
  34. GRB020603, BVRcIc field observations
  35. GRB020531, BVRcIc field photometry
  36. GRB020531 Optical Observations
  37. GRB020531: Observations with the Chandra X-ray Observatory
  38. GRB020531, optical observations
  39. GRB020531: optical observations
  40. GRB020531(=H2042): Optical Observations
  41. GRB020531(=H2042): Optical Observations
  42. GRB020531: Optical observations
  43. GRB020531(=H2042): A Short, Hard Burst Localized by HETE
  44. GRB020525, optical observations
  45. HETE Observations of GX354-0 (= MXB1728-34, so-called "Slow
  46. XRF020427: Chandra Identification of a Likely X-ray Counterpart
  47. HST detection of the likely host galaxy of GRB 020124
  48. GRB020405 field photometry at ESO
  49. XRF020427: Chandra Observations and Candidate X-ray Counterparts
  50. GRB(XRF) 020427: X-ray afterglow with BeppoSAX
  51. GRB020321 : Optical observations.
  52. XRF 020427
  53. GRB 020124: Optical observations
  54. IPN triangulation of GRB020418
  55. GRB020405: VLT observations of the OT environment
  56. IPN triangulation of GRB020413
  57. GRB020405: predicted break
  58. GRB 020409: No Evidence for an Optical Afterglow
  59. GRB 020331 Kyoto observation on March 31
  60. GRB020410: BeppoSAX NFI observation
  61. X-ray afterglow of GRB020321
  62. GRB020331 optical observations with RIMOTS
  63. GRB020124 optical observations with RIBOTS/RIMOTS
  64. GRB 020321: Candidate X-ray Counterparts
  65. GRB020406(?), optical observations
  66. GRB 020405: Decay index
  67. Short RXTE/ASM transient 020406; may be a GRB
  68. GRB020405, Radio Observations
  69. GRB 020405, U-band observations
  70. GRB011212: Optical Observations
  71. GRB 020331: NIR Observations
  72. GRB020331 NIR observation at KPNO (re-submission)
  73. GRB02033 NIR observation at KPNO
  74. GRB020331 field photometry
  75. GRB 020331, NIR observations
  76. GRB020331(=H1963): The "Easter" Burst Detected by HETE
  77. GRB 020322: BeppoSAX observations of the X-ray afterglow
  78. GRB011211: HST Observations of Optical Afterglow and Host Galaxy
  79. Near-Infrared Observations of GRB020322 at TIRGO
  80. GRB 020321, Radio Observations
  81. GRB 020322: Optical Observations
  82. GRB020127: Proposed Host Galaxy Detection and Identification of Afterglow
  83. GRB 020321: Optical observations
  84. GRB020317 BVRI field photometry
  85. GRB011211 revised BVRI field photometry
  86. GRB020305 BVRI field photometry
  87. GRB020322 BVRI field photometry
  88. GRB 020322: Optical Sources and Improved Astrometry
  89. GRB020317: optical observations
  90. GRB020321 optical observations
  91. GRB020321: a faint BeppoSAX detection
  92. GRB 020317 : KISO Optical Observations
  93. GRB020317 (=H1959): Localization by HETE of a Low Fluence GRB
  94. GRB 020305: Optical Observations
  95. GRB020317, optical observations
  96. GRB 020317: Optical observations
  97. GRB 011121: Third HST Epoch
  98. GRB020305: Properties of the Candidate Optical Afterglow
  99. GRB 011121: HST Observations reveal an intermediate-time multicolor
  100. GRB011130 (XRF011130) Second Epoch Chandra Observations

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