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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.

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

45653 results found.

  1. GRB 070227: optical observations
  2. GRB 070223: Optical Observations
  3. GRB 070227: optical observations
  4. GRB 070227: Swift/UVOT Upper Limits
  5. GRB 070227: TAROT La Silla observatory optical observations
  6. GRB 070227, Swift-BAT refined analysis
  7. GRB070227: possible X-ray afterglow detection
  8. GRB 070227: Swift detection of a burst in ground analysis
  9. GRB 920925C: optical afterglow candidate
  10. GRB 070224: Optical afterglow confirmation
  11. IBAS Alert n. 4144: not a GRB
  12. GRB 070224: Swift/UVOT Upper Limits
  13. GRB070224: Swift-XRT Astrometrically Corrected Position
  14. VLA observation of GRB 070223
  15. VLA observation of GRB 070220
  16. GRB070224: Magellan Imaging Observations
  17. GRB 070224: WHT K-band imaging
  18. GRB 070224: MDM Observations
  19. GRB070224: Gemini Imaging Observations
  20. GRB 070224: SARA upper limit
  21. GRB070224: Swift-XRT Refined Analysis
  22. GRB 070224: optical afterglow candidate
  23. GRB 070224, Swift-BAT refined analysis
  24. GRB 070224: MASTER-Net refind analysis
  25. GRB 070224: MASTER-VWF-Kislovodsk observations
  26. GRB 070224: MASTER observations
  27. GRB 070224: Swift detection of a burst
  28. GRB 070223: Optical observations
  29. RHESSI Spectrum of GRB070220
  30. GRB070223: Swift/UVOT refined analysis
  31. GRB 070223: Optical-IR observation with KANATA
  32. GRB 070223, Swift-BAT refined analysis
  33. GRB070223: MASTER-VWF-Kislovodsk observations
  34. GRB 070223: Swift-XRT Refined Analysis
  35. GRB 070220: pseudo-z~2.15 from spectral parameters of the prompt
  36. GRB070223 - SDSS Pre-Burst Observations
  37. GRB 070223: Liverpool Telescope Possible Afterglow Candidate
  38. GRB 070223: MDM Observations
  39. GRB070223: Swift burst
  40. Konus-Wind and Konus-A observations of GRB 070220
  41. GRB 070220: MITSuME Okayama Optical Observation
  42. GRB 070220: ART-3 Optical and NIR limits
  43. GRB 070220 Swift-BAT Refined Analysis
  44. Swift/UVOT refined analysis of GRB070220
  45. GRB 070209: Swift XRT refined analysis
  46. GRB 070220: Swift-XRT Refined Analysis
  47. GRB 070220: Observation with the KANATA 1.5m telescope
  48. GRB 070219: Gemini Observations
  49. GRB 070220 : Faulkes Telescope North optical limit
  50. GRB 070220: Swift detection of a burst
  51. GRB070219: MASTER-VWF-Kislovodsk observations
  52. GRB 070219: XRT Refined Analysis
  53. GRB 070219: Swift/UVOT Upper limits
  54. GRB 070219: I-band observations
  55. GRB 070219, Swift-BAT refined analysis
  56. GRB 070219: optical TNG observations
  57. GRB 070219: Liverpool Telescope Observations
  58. GRB 070219: ROTSE-III Optical Limits
  59. GRB070219 - SDSS Pre-Burst Observations
  60. GRB 070219: Swift detection of a burst
  61. IPN triangulation of GRB070201 (refined error box using MESSENGER data)
  62. GRB 070125 observations with the GMRT
  63. GRB 070209: Redshift of a galaxy in the error circle of XRT source
  64. Swift-BAT trigger 260304 is NOT a burst or transient
  65. GRB 060927: PROMPT Observations
  66. GRB 070201: Correction to GCN 6094
  67. GRB 070129: MDM I-band Detection
  68. GRB 070125: Break in Optical Decay
  69. GRB 070209: Swift XRT analysis
  70. GRB 070201: clarification on localization and Konus-Wind spectra
  71. GRB070208: optical observations
  72. GRB 070201: IPN constraints and nearby galaxies
  73. GRB 070201: Proximity of IPN annulus to M31
  74. GRB 070208: MARGE Optical Observations
  75. IPN localization of very bright long hard GRB 070207
  76. IPN localization of very intense short GRB 070201
  77. GRB 070209, Swift-BAT refined analysis of the short hard burst
  78. GRB 070209: Swift detection of a short hard burst
  79. GRB 070208: Swift XRT refined analysis
  80. GRB 070208: RAPTOR detection of early afterglow onset
  81. GRB070208: Absorption and emission redshift from Gemini
  82. GRB 070208: MDM Optical Decay
  83. GRB 070208, Swift-BAT refined analysis
  84. GRB070208 - SDSS Pre-Burst Observations
  85. GRB 070208: Early IR detection and afterglow astrometry
  86. GRB 070208: Afterglow confirmation from P60
  87. GRB070208: Faulkes Telescope North Afterglow Identification
  88. GRB 070208: ROTSE-III Optical Limits
  89. GRB 070208: MDM Observations
  90. GRB 070208: Swift detection of a burst
  91. GRB 070125 detection with CARMA
  92. Swift-BAT trigger 259527 is a Cosmic Ray Shower
  93. GRB 070125: Redshift z>~1.54 from Gemini Afterglow Spectrum
  94. GRB 070129: afterglow confirmation
  95. GRB070124: Swift-XRT Follow-up Observation
  96. GRB070126: Swift-XRT Observation
  97. GRB 070125: further AAVSO optical observations
  98. GRB 070129: Swift/UVOT Upper limits
  99. GRB 070129: dust-scattered X-ray halo detected by Swift/XRT
  100. GRB 070125: optical observation

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