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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"

2722 results found.

  1. GRB 060116: PROMPT Observations
  2. GRB 060105: Radio observations
  3. GRB 060102 - no XRT afterglow
  4. GRB 051210: Swift/UVOT upper limits
  5. GRB051210: Swift UVOT Observation
  6. GRB 051210: Swift detection of a burst
  7. GRB051111: Swift/UVOT Observations
  8. GRB 051111: Swift-BAT refined analysis
  9. GRB051103: MASTER: OT limit and host galaxy candidates
  10. GRB051028: Swift-XRT refined analysis
  11. GRB051105A: Swift/UVOT Observations
  12. GRB051103:_MASTER_optical_observations
  13. GRB051028: WHT optical candidate
  14. GRB051028: Swift XRT Position
  15. SGR 1806-20: continued moderate activity seen with INTEGRAL
  16. GRB051012: Swift-XRT analysis
  17. GRB 051021B: Refined analysis of the Swift-BAT burst
  18. GRB 051021: SOAR NIR Observations
  19. Swift-BAT triggered on a posible CR Shower or possible GRB
  20. GRB 051012: Swift-BAT detection of burst yesterday
  21. GRB 050922B: optical limit
  22. GRB 050906: Possible X-ray Counterpart
  23. GRB 050906: MARGE Optical Limits
  24. GRB 050824: MDM Observations
  25. GRB050824: First 2 hours of power low optical decay?
  26. GRB050824: MASTER final analysis of the OT observations
  27. GRB050822: Swift/UVOT upper limits
  28. GRB050813: Maidanak I-band observations
  29. GRB 050822: Swift detection of a long burst
  30. GRB050807(=H3889): An X-Ray Rich GRB Localized by HETE
  31. GRB050803: CrAO optical observations, no OT candidate
  32. GRB 050805b: OHP optical limits
  33. GRB 050803: Magellan Observations
  34. GRB 050803: early Swift XRT analysis results
  35. GRB 050730: OHP optical observations
  36. GRB 050802: early Swift XRT analysis results
  37. GRB 050802: Swift/UVOT observations
  38. GRB 050802: XRT position
  39. Swift-BAT trigger 147918 is not a real GRB
  40. Swift BAT Trigger 146986 is SWIFT J1753.5-0127
  41. GRB050716, optical observation
  42. GRB 050713, R-band observations at NOT
  43. GRB050607: prompt REM observations
  44. GRB050525: Super-LOTIS observations
  45. GRB 050525: Optical observation
  46. XRF050522: NIR observations of XRT candidate
  47. XRF 050522: Swift XRT refined analysis
  48. GRB050502b: Early Observation
  49. GRB 050505, early TAROT observation
  50. GRB050509a: Swift UVOT observations
  51. GRB 050509a: Swift XRT Position
  52. Swift Detection of the Burst GRB050509
  53. GRB 050505: Keck I-band Magnitude
  54. GRB 050505: early time observations
  55. GRB (?) 050504: IR Observations, Intriguing Source
  56. GRB050326: optical limit
  57. Swift Detection of GRB 050319
  58. RXTE Observations of GRB050318
  59. GRB050309: CONCAM pre-trigger and trigger coincident optical
  60. GRB050215b: Faulkes North and SDSS limits on UKIRT candidate
  61. GRB 050219b: Swift XRT Position
  62. GRB050215b: Swift UVOT Detection of Afterglow Emission
  63. GRB 050215b: XRT confirmation of IR afterglow candidate
  64. GRB 050215B: candidate afterglow
  65. GRB 050215B: UKIRT K-band imaging
  66. GRB 050215b: Swift XRT Observations
  67. GRB050126: MASTER optical limit for KECK OT
  68. GRB050126: MASTER optical observations
  69. GRB050117: Palomar WIRC Ks-band observations
  70. GRB 041217: Optical observations
  71. GRB041226: ROTSE-III Optical Observations
  72. GRB041218: Continued P60 Optical Observations
  73. GRB 041218: Optical observations
  74. GRB041211,optical observation
  75. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  76. SGR 1806-20 still active
  77. GRB040924,optical observation
  78. IBAS GRB Alerts 1978-1980
  79. GRB040903 - A XRF?
  80. XRF040812: GMRT observations
  81. GRB 040812: Optical counterparts of CXO sources
  82. GRB 040812: Keck and LCO optical observations
  83. GRB 040812: Keck and LCO observations
  84. GRB040624: optical monitoring at TNG
  85. XRF040701: Second-Epoch Chandra Observations
  86. XRF040701: VLA Observations
  87. XRF040701: First-Epoch Chandra Observations
  88. IPN Summary of SGR1806-20 Activity in 2004
  89. MASTER: HETE Alert 3274 optical observation
  90. GRB040511: Candidate optical/NIR afterglow
  91. GRB 040319 (=H3128): An X-Ray-Rich GRB Localized by the HETE-2 WXM and SXC
  92. GRB 040228 (=H3066?,=H3067?): A Long GRB Localized by the HETE-2 WXM
  93. GRB031220: 2nd Chandra observation and X-ray afterglow candidate
  94. GRB040106: refined X-ray transient position
  95. GRB040106, Radio Observations
  96. GRB040106, likely optical afterglow
  97. GRB 040106: Optical observations
  98. XMM-Newton observation of GRB040106
  99. GRB 040106 : Planned XMM-Newton observation
  100. GRB 040106 : a long GRB detected with INTEGRAL

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