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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"

24994 results found.

  1. GRB 020812: optical observation at Kyoto University
  2. Second epoch K band imaging of GRB 020819
  3. GRB 020813 : HST observations
  4. GRB 020812: early time optical observation at Ouda Station
  5. GRB020813: Magellan BVRI Photometry
  6. GRB 020819: Optical observations
  7. K band observation of GRB 020819
  8. GRB020813: optical and NIR observations
  9. GRB020813: Fading X-ray Afterglow Observed with Chandra
  10. GRB020813, UBVRI field calibration
  11. GRB020812: NIR observations
  12. Polarimetry of GRB020813: evidence for variability
  13. GRB020813 IRAM millimeter observations
  14. GRB020812: optical observations
  15. GRB020813: High-Resolution Optical Observations
  16. GRB 020812: optical observation at Bisei
  17. GRB020813: Early Time Magnitude
  18. Millimeter observation of GRB 020813
  19. GRB020812: optical observations
  20. GRB 020813 : KISO multiband optical observations
  21. GRB020813, optical observations
  22. IPN error box for GRB020813
  23. GRB020813, astrometric position
  24. Spectropolarimetry of GRB 020813
  25. GRB 020812 optical observation
  26. GRB020812(=H2257): A Long Burst Localized by HETE in Near-Real Time
  27. GRB020801: Imaging of Suggested OT Counterpart at the Magellan
  28. HST Imaging of the Host of GRB 011121
  29. GRB020801, optical afterglow candidate
  30. GRB020331: Late-time Optical Light Curve (re-submission)
  31. GRB020331: Late-time Optical Light Curve
  32. IPN triangulation of GRB020714
  33. IPN triangulation of GRB020715 (=GRB150702)
  34. IPN triangulation of GRB020714
  35. IPN triangulation of GRB150702
  36. GRB 020410: Discovery of Probable OT by HST
  37. GRB 020124, HST observations of the fading afterglow
  38. IPN triangulation of GRB020708
  39. IPN triangulation of GRB020708
  40. Correction to IPN error box for GRB020706
  41. IPN triangulation of GRB020706
  42. GRB 020705: Optical observations
  43. GRB 020625, optical observations
  44. GRB 020625: Optical observations
  45. GRB 020531: optical photometry of Chandra sources
  46. GRB020625 (=H2081): A Long Burst Localized by HETE
  47. The Probable Host Galaxy of GRB/XRF 020427
  48. GRB/XRF 020427, detection of an underlying system with the VLT
  49. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  50. AXP 1E2259+586 optical observations
  51. Fading Optical Source in the Field of GRB020531
  52. GRB 020531, INT+WFC deep optical upper limits
  53. SGR-like Bursts from the AXP 1E 2259+586
  54. GRB020405: polarimetric observations
  55. GRB 020531, simultaneous optical observations
  56. GRB 020531/Candidate Redshift
  57. GRB020531: Detection of Candidate Host Galaxy
  58. GRB020531: Second epoch Chandra observations
  59. GRB020604, optical observations
  60. GRB020604, BVRcIc field photometry
  61. GRB020603, BVRcIc field observations
  62. GRB020531, BVRcIc field photometry
  63. GRB020531 Optical Observations
  64. GRB020531: Observations with the Chandra X-ray Observatory
  65. GRB020531, optical observations
  66. GRB020531: optical observations
  67. GRB020531(=H2042): Optical Observations
  68. GRB020531(=H2042): Optical Observations
  69. GRB020531: Optical observations
  70. GRB020531(=H2042): A Short, Hard Burst Localized by HETE
  71. GRB020525, optical observations
  72. HETE Observations of GX354-0 (= MXB1728-34, so-called "Slow
  73. XRF020427: Chandra Identification of a Likely X-ray Counterpart
  74. HST detection of the likely host galaxy of GRB 020124
  75. GRB020405 field photometry at ESO
  76. XRF020427: Chandra Observations and Candidate X-ray Counterparts
  77. GRB(XRF) 020427: X-ray afterglow with BeppoSAX
  78. GRB020321 : Optical observations.
  79. XRF 020427
  80. GRB 020124: Optical observations
  81. IPN triangulation of GRB020418
  82. GRB020405: VLT observations of the OT environment
  83. IPN triangulation of GRB020413
  84. GRB020405: predicted break
  85. GRB 020409: No Evidence for an Optical Afterglow
  86. GRB 020331 Kyoto observation on March 31
  87. GRB020410: BeppoSAX NFI observation
  88. X-ray afterglow of GRB020321
  89. GRB020331 optical observations with RIMOTS
  90. GRB020124 optical observations with RIBOTS/RIMOTS
  91. GRB 020321: Candidate X-ray Counterparts
  92. GRB020406(?), optical observations
  93. GRB 020405: Decay index
  94. Short RXTE/ASM transient 020406; may be a GRB
  95. GRB020405, Radio Observations
  96. GRB 020405, U-band observations
  97. GRB011212: Optical Observations
  98. GRB 020331: NIR Observations
  99. GRB020331 NIR observation at KPNO (re-submission)
  100. GRB02033 NIR observation at KPNO

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