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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"

37525 results found.

  1. GRB 051109B : Lulin Optical Observations
  2. GRB 051109A : Lulin BVRI Optical afterglow observation
  3. GRB 051109a: BOOTES R & I-band detection of the early afterglow
  4. GRB051109B: XRT position
  5. GRB 051109B: Super-LOTIS Observations
  6. GRB 051109B Kiso optical follow-up observation
  7. GRB 051109B: Swift detection of a burst
  8. GRB 051109: HET Optical Spectrum and Absorption Redshift
  9. GRB 051109: PROMPT Detections
  10. GRB 051109: Rc and Ic observations
  11. GRB 051109: Swift-BAT refined analysis
  12. GRB 051109a: IR Photometry and Astrometry
  13. GRB 051109a: MDM Observations
  14. GRB 051109A: ROTSE-III Decline rate for Optical Counterpart
  15. GRB 051109a: IR Detections
  16. GRB 051109: ROTSE-III Detection of Possible Counterpart
  17. GRB051105B: Swift/XRT upper limit
  18. GRB051105B: Swift/UVOT upper limit
  19. GRB051103: optical observations
  20. GRB 051103, optical observations
  21. GRB051103: MASTER: OT limit and host galaxy candidates
  22. GRB 051105a, observation from Naini Tal and OSN
  23. GRB 051105A, 2nd epoch optical observations
  24. GRB 051105a: MDM Observations
  25. GRB 051105A: TNG optical observations
  26. GRB051105A: Swift/UVOT Observations
  27. GRB 051105A, radio observations
  28. GRB051103:_MASTER_optical_observations
  29. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  30. GRB 051105A, optical observations
  31. XRT observations of GRB 051105A
  32. GRB 051105: Swift-BAT improved refined analysis
  33. GRB 051105b: ART optical limits
  34. GRB051105B - A long GRB detected by INTEGRAL
  35. GRB 051105B (INTEGRAL 2701): Optical observation
  36. GRB 051105: Swift-BAT refined analysis
  37. GRB 051105: Optical limit
  38. GRB 051105: Swift detection of a short burst
  39. IBAS Alert 2700: Not a GRB
  40. GRB 051016B host spectroscopy and redshift
  41. GRB051016B: optical observation
  42. Recent GRB UBVRcIc field photometry
  43. Konus-Wind observation of GRB 051028
  44. GRB051028:MASTER correction and final results
  45. GRB 051022: RTT150 optical observations
  46. GRB 051021A: RTT150 optical observations
  47. GRB051028 SARA Observation
  48. GRB051028: optical observations
  49. GRB051028: Swift/UVOT upper limits
  50. GRB051028: confirmation of the afterglow
  51. GRB051028: WHT optical candidate
  52. GRB051028: Swift XRT Position
  53. GRB051028:MASTER observations
  54. GRB 051028 (=H3951): A GRB localized by HETE
  55. GRB051028:MASTER optical observations
  56. GRB 051022: XRT Refined Spectral and Temporal Analysis--Correction
  57. GRB051022: Swift XRT measurement of jet break
  58. GRB051021B: Swift/UVOT Upper limits
  59. GRB 051021, Optical Observations
  60. GRB 051022: XRT Refined Spectral and Temporal Analysis
  61. GRB 051022, refined optical astrometry
  62. Chandra Observations of GRB 051022
  63. GRB 051022 Chandra Observations scheduled
  64. GRB051021a: optical observations
  65. GRB 051022: WSRT Radio Detection
  66. GRB 051022, mm counterpart
  67. GRB051022: host galaxy redshift
  68. GRB 051022: Swift/UVOT Upper Limits
  69. GRB051022: Radio Counterpart
  70. GRB 051022: SOAR JKs Observations
  71. Konus-Wind observation of GRB 051022
  72. GRB051022: Optical Observations
  73. GRB 051022: Magellan NIR imaging
  74. GRB 051021: PROMPT RcIc Observations
  75. GRB051021b: Magellan IR Imaging
  76. GRB 051022: Spectral Analysis Indicates That The Spectrum Is Absorbed
  77. GRB 051021: Correction
  78. GRB 051022, J & K-band observation
  79. GRB 051021, SMARTS optical/IR observations
  80. GRB 051021: P200 Ks Observations
  81. IPN triangulation of GRB051022 (=H3950)
  82. GRB 051021: MDM Upper Limit
  83. GRB 051022 (=H3950): SXC Flight Localization is Valid
  84. GRB051021: Swift/UVOT Upper Limits
  85. GRB 051021B: Refined analysis of the Swift-BAT burst
  86. GRB 051022: SSO40 Optical Observations
  87. GRB 051022A: ROTSE-III Optical Limits
  88. GRB051022 (=H3590), A GRB Detected By HETE
  89. GRB 051022: Optical observations
  90. GRB 051021,optical observation
  91. GRB051021B: Swift XRT Position
  92. GRB 051021: SOAR NIR Observations
  93. GRB 051021B: Swift detection of a burst
  94. GRB051021 (=H3947): Refined Analysis
  95. GRB 051021 : optical afterglow observation at Lulin
  96. GRB 051021: Optical observations
  97. GRB 051021: ROTSE-III Confirmation of Optical Counterpart
  98. GRB 051021: Optical observations and candidate afterglow
  99. GRB051021.63
  100. GRB051021.6: MASTER optical observation

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