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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"

24682 results found.

  1. GRB031203: Planned XMM-Newton observation
  2. GRB 031203: further analysis of INTEGRAL data
  3. GRB 030329: Planned XMM-Newton Observation
  4. GRB 031111B (= H2925) : Kyoto Optical Observation
  5. IPN triangulation of GRB031114 (large error box)
  6. GRB 031111, optical observations
  7. GRB031026: 1.2mm upper limit with MAMBO at the IRAM 30m
  8. GRB030929/SN2003jd association unlikely based on IPN localiztion
  9. IPN triangulation of GRB031027 (small error box)
  10. Lulin optical follow-up observations of GRB031026
  11. GRB 031026 (=H2882): Evidence for High Redshift from Prompt
  12. IPN triangulation of GRB031024 (single error box)
  13. IPN triangulation of GRB031024 (annulus)
  14. IPN triangulation of GRB031020 (large error box)
  15. XRF 030824: additional observations at CFHT
  16. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  17. XRF 030723: Subaru Optical Observations
  18. XRF 030824: Early follow-up observation at Kiso observatory
  19. XRF 030824: observations at CFHT
  20. IPN triangulation of GRB030922B (large error box)
  21. XRF 030723: Detection of the likely host galaxy
  22. XRF030824 (=H2821): An X-Ray Flash Localized by the HETE WXM
  23. XRF030823 (=H2818): An X-Ray Flash Localized by the HETE WXM and SXC
  24. IPN triangulation of GRB030921 (large error box)
  25. IPN triangulation of GRB030919 (large error box)
  26. GRB030913: Subaru Optical Observations
  27. GRB 030913, optical candidate
  28. GRB 030913, BOOTES observations
  29. IPN triangulation of GRB030916 (possible short/hard GRB; large error box)
  30. GRB030913: wide field imaging (7 sq.deg) of the error box by MASTER
  31. XRF 020427: Gemini-South Spectroscopic Observations of the Host
  32. XRF030824: Optical observations
  33. IPN triangulation of GRB030903 (large error box)
  34. IPN triangulation of GRB030827 (large error box)
  35. GRB030823: optical observations
  36. GRB030823: optical observation at Tokyo Tech
  37. Lulin follow-up observations of GRB030823
  38. GRB 030821(=H2814): A Faint, Long GRB Localized by the HETE WXM and the IPN
  39. IPN detection of continued activity from SGR1806-20
  40. GRB 030817 = H2808 TAROT optical observations
  41. SGR 1808-20 (=H2802): A Possible new SGR
  42. XRF030723(=H2777): Chandra Fading X-ray Afterglow Confirmed
  43. XRF 030723: Detection of a rebrightening in the optical afterglow
  44. XRF030723, BVRcIc field photometry update
  45. IPN triangulation of GRB030801 (large error box)
  46. GRB021206 optical counterpart upper limit
  47. IPN triangulation of GRB030726 (large error box)
  48. IPN triangulation of GRB030721 (large error box)
  49. XRF030723 Radio Observations
  50. XRF 030723: confirmation of fading optical counterpart
  51. XRF030723(=H2777): Chandra Observations
  52. GRB030723: Upper limits from historical observations
  53. XRF030723: Palomar observations and proposed counterpart
  54. GRB030725 (=H2779): A Bright GRB Localized by HETE
  55. XRF030723 (= H2777): Chandra Observations Scheduled
  56. XRF030723, BVRcIc field photometry correction
  57. XRF030723, ROTSE-III Early Observations
  58. XRF030723, BVRcIc field photometry
  59. XRF 030723, optical observations
  60. XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and
  61. Konus-Wind detection of the bursts from SGR1806-20 region
  62. SGR 1806-20, submm observations
  63. RXTE PCA Observations of SGR1806-20 Region
  64. IPN triangulation of GRB030714 (two large error boxes)
  65. IPN triangulation of GRB030715 (two large error boxes)
  66. GRB030706 triangulation (single large error box)
  67. GRB030329, optical observation in May
  68. IPN triangulation of GRB030626 (single large error box)
  69. IPN triangulation of GRB030626 (two large error boxes)
  70. GRB030329: second XMM-Newton observation
  71. GRB030329 -- RATAN-600 data in April-May
  72. GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
  73. IPN triangulation of GRB030606 (two alternate error boxes)
  74. GRB 030528: Infrared Observations and the Proposed IR Counterpart
  75. GRB 030528: tentative NIR counterpart
  76. GRB030528(=H2724): Observations with the Chandra X-ray Observatory
  77. GRB030528, BVRI field photometry
  78. GRB030329, SPM optical observations
  79. GRB030528: Chandra TOO Planned
  80. GRB030528(=H2724): Revised SXC Localization
  81. GRB 030528 Bisei optical observation
  82. GRB030528 (H2724): A long GRB localized by HETE
  83. GRB 030329: Correction to GCN 2254
  84. GRB 030329: Optical Observations
  85. GRB 030528 (=H2724) Kyoto optical observation
  86. GRB 030416: Optical Observations
  87. GRB 030329 Optical Observations
  88. GRB030329: XMM-Newton observation
  89. GRB 021004: HST observations
  90. GRB030324: Further Observations of the Candidate Optical Afterglow
  91. GRB030519B (=H2716): Peak Fluxes, Fluences, and Energy Spectrum
  92. IPN triangulation of GRB030519B=H2716 (small error box)
  93. HETE GRB030329, correction to Rc Observations in Loiano
  94. GRB 030329: Optical limit (contemporaneous imaging)
  95. IPN triangulation of GRB030509 (small errror box)
  96. GRB030329, BVRI photometry
  97. GRB030429, refiend optical brightness
  98. GRB 030329: Optical limit (contemporaneous photography)
  99. GRB030418, BVRcIc field photometry
  100. GRB030429, BVRcIc field photometry

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