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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').
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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

24606 results found.

  1. Confirmation of IPN error box for GRB020910
  2. IPN triangulation of GRB020910
  3. IPN GCN Circulars now to be issued without restriction
  4. Single IPN error box for GRB020904
  5. XRF 020903: optical observation at Kyoto
  6. GRB020322 : HST/STIS observations
  7. XRF 020903: Optical observations
  8. IPN triangulation of GRB020904
  9. INTEGRAL GRBs added to GCN
  10. SGR1900+14 burst localized by HETE
  11. GRB020813: High-resolution optical spectroscopy
  12. GRB020812: negative optical observations
  13. GRB 020812: optical observation at Kyoto University
  14. Second epoch K band imaging of GRB 020819
  15. GRB 020813 : HST observations
  16. GRB 020812: early time optical observation at Ouda Station
  17. GRB020813: Magellan BVRI Photometry
  18. GRB 020819: Optical observations
  19. K band observation of GRB 020819
  20. GRB020813: optical and NIR observations
  21. GRB020813: Fading X-ray Afterglow Observed with Chandra
  22. GRB020813, UBVRI field calibration
  23. GRB020812: NIR observations
  24. Polarimetry of GRB020813: evidence for variability
  25. GRB020813 IRAM millimeter observations
  26. GRB020812: optical observations
  27. GRB020813: High-Resolution Optical Observations
  28. GRB 020812: optical observation at Bisei
  29. GRB020813: Early Time Magnitude
  30. Millimeter observation of GRB 020813
  31. GRB020812: optical observations
  32. GRB 020813 : KISO multiband optical observations
  33. GRB020813, optical observations
  34. IPN error box for GRB020813
  35. GRB020813, astrometric position
  36. Spectropolarimetry of GRB 020813
  37. GRB 020812 optical observation
  38. GRB020812(=H2257): A Long Burst Localized by HETE in Near-Real Time
  39. GRB020801: Imaging of Suggested OT Counterpart at the Magellan
  40. HST Imaging of the Host of GRB 011121
  41. GRB020801, optical afterglow candidate
  42. GRB020331: Late-time Optical Light Curve (re-submission)
  43. GRB020331: Late-time Optical Light Curve
  44. IPN triangulation of GRB020714
  45. IPN triangulation of GRB020715 (=GRB150702)
  46. IPN triangulation of GRB020714
  47. IPN triangulation of GRB150702
  48. GRB 020410: Discovery of Probable OT by HST
  49. GRB 020124, HST observations of the fading afterglow
  50. IPN triangulation of GRB020708
  51. IPN triangulation of GRB020708
  52. Correction to IPN error box for GRB020706
  53. IPN triangulation of GRB020706
  54. GRB 020705: Optical observations
  55. GRB 020625, optical observations
  56. GRB 020625: Optical observations
  57. GRB 020531: optical photometry of Chandra sources
  58. GRB020625 (=H2081): A Long Burst Localized by HETE
  59. The Probable Host Galaxy of GRB/XRF 020427
  60. GRB/XRF 020427, detection of an underlying system with the VLT
  61. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  62. AXP 1E2259+586 optical observations
  63. Fading Optical Source in the Field of GRB020531
  64. GRB 020531, INT+WFC deep optical upper limits
  65. SGR-like Bursts from the AXP 1E 2259+586
  66. GRB020405: polarimetric observations
  67. GRB 020531, simultaneous optical observations
  68. GRB 020531/Candidate Redshift
  69. GRB020531: Detection of Candidate Host Galaxy
  70. GRB020531: Second epoch Chandra observations
  71. GRB020604, optical observations
  72. GRB020604, BVRcIc field photometry
  73. GRB020603, BVRcIc field observations
  74. GRB020531, BVRcIc field photometry
  75. GRB020531 Optical Observations
  76. GRB020531: Observations with the Chandra X-ray Observatory
  77. GRB020531, optical observations
  78. GRB020531: optical observations
  79. GRB020531(=H2042): Optical Observations
  80. GRB020531(=H2042): Optical Observations
  81. GRB020531: Optical observations
  82. GRB020531(=H2042): A Short, Hard Burst Localized by HETE
  83. GRB020525, optical observations
  84. HETE Observations of GX354-0 (= MXB1728-34, so-called "Slow
  85. XRF020427: Chandra Identification of a Likely X-ray Counterpart
  86. HST detection of the likely host galaxy of GRB 020124
  87. GRB020405 field photometry at ESO
  88. XRF020427: Chandra Observations and Candidate X-ray Counterparts
  89. GRB(XRF) 020427: X-ray afterglow with BeppoSAX
  90. GRB020321 : Optical observations.
  91. XRF 020427
  92. GRB 020124: Optical observations
  93. IPN triangulation of GRB020418
  94. GRB020405: VLT observations of the OT environment
  95. IPN triangulation of GRB020413
  96. GRB020405: predicted break
  97. GRB 020409: No Evidence for an Optical Afterglow
  98. GRB 020331 Kyoto observation on March 31
  99. GRB020410: BeppoSAX NFI observation
  100. X-ray afterglow of GRB020321

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