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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"

25089 results found.

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

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