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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"

24871 results found.

  1. IPN triangulation of GRB031024 (single error box)
  2. IPN triangulation of GRB031024 (annulus)
  3. IPN triangulation of GRB031020 (large error box)
  4. XRF 030824: additional observations at CFHT
  5. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  6. XRF 030723: Subaru Optical Observations
  7. XRF 030824: Early follow-up observation at Kiso observatory
  8. XRF 030824: observations at CFHT
  9. IPN triangulation of GRB030922B (large error box)
  10. XRF 030723: Detection of the likely host galaxy
  11. XRF030824 (=H2821): An X-Ray Flash Localized by the HETE WXM
  12. XRF030823 (=H2818): An X-Ray Flash Localized by the HETE WXM and SXC
  13. IPN triangulation of GRB030921 (large error box)
  14. IPN triangulation of GRB030919 (large error box)
  15. GRB030913: Subaru Optical Observations
  16. GRB 030913, optical candidate
  17. GRB 030913, BOOTES observations
  18. IPN triangulation of GRB030916 (possible short/hard GRB; large error box)
  19. GRB030913: wide field imaging (7 sq.deg) of the error box by MASTER
  20. XRF 020427: Gemini-South Spectroscopic Observations of the Host
  21. XRF030824: Optical observations
  22. IPN triangulation of GRB030903 (large error box)
  23. IPN triangulation of GRB030827 (large error box)
  24. GRB030823: optical observations
  25. GRB030823: optical observation at Tokyo Tech
  26. Lulin follow-up observations of GRB030823
  27. GRB 030821(=H2814): A Faint, Long GRB Localized by the HETE WXM and the IPN
  28. IPN detection of continued activity from SGR1806-20
  29. GRB 030817 = H2808 TAROT optical observations
  30. SGR 1808-20 (=H2802): A Possible new SGR
  31. XRF030723(=H2777): Chandra Fading X-ray Afterglow Confirmed
  32. XRF 030723: Detection of a rebrightening in the optical afterglow
  33. XRF030723, BVRcIc field photometry update
  34. IPN triangulation of GRB030801 (large error box)
  35. GRB021206 optical counterpart upper limit
  36. IPN triangulation of GRB030726 (large error box)
  37. IPN triangulation of GRB030721 (large error box)
  38. XRF030723 Radio Observations
  39. XRF 030723: confirmation of fading optical counterpart
  40. XRF030723(=H2777): Chandra Observations
  41. GRB030723: Upper limits from historical observations
  42. XRF030723: Palomar observations and proposed counterpart
  43. GRB030725 (=H2779): A Bright GRB Localized by HETE
  44. XRF030723 (= H2777): Chandra Observations Scheduled
  45. XRF030723, BVRcIc field photometry correction
  46. XRF030723, ROTSE-III Early Observations
  47. XRF030723, BVRcIc field photometry
  48. XRF 030723, optical observations
  49. XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and
  50. Konus-Wind detection of the bursts from SGR1806-20 region
  51. SGR 1806-20, submm observations
  52. RXTE PCA Observations of SGR1806-20 Region
  53. IPN triangulation of GRB030714 (two large error boxes)
  54. IPN triangulation of GRB030715 (two large error boxes)
  55. GRB030706 triangulation (single large error box)
  56. GRB030329, optical observation in May
  57. IPN triangulation of GRB030626 (single large error box)
  58. IPN triangulation of GRB030626 (two large error boxes)
  59. GRB030329: second XMM-Newton observation
  60. GRB030329 -- RATAN-600 data in April-May
  61. GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
  62. IPN triangulation of GRB030606 (two alternate error boxes)
  63. GRB 030528: Infrared Observations and the Proposed IR Counterpart
  64. GRB 030528: tentative NIR counterpart
  65. GRB030528(=H2724): Observations with the Chandra X-ray Observatory
  66. GRB030528, BVRI field photometry
  67. GRB030329, SPM optical observations
  68. GRB030528: Chandra TOO Planned
  69. GRB030528(=H2724): Revised SXC Localization
  70. GRB 030528 Bisei optical observation
  71. GRB030528 (H2724): A long GRB localized by HETE
  72. GRB 030329: Correction to GCN 2254
  73. GRB 030329: Optical Observations
  74. GRB 030528 (=H2724) Kyoto optical observation
  75. GRB 030416: Optical Observations
  76. GRB 030329 Optical Observations
  77. GRB030329: XMM-Newton observation
  78. GRB 021004: HST observations
  79. GRB030324: Further Observations of the Candidate Optical Afterglow
  80. GRB030519B (=H2716): Peak Fluxes, Fluences, and Energy Spectrum
  81. IPN triangulation of GRB030519B=H2716 (small error box)
  82. HETE GRB030329, correction to Rc Observations in Loiano
  83. GRB 030329: Optical limit (contemporaneous imaging)
  84. IPN triangulation of GRB030509 (small errror box)
  85. GRB030329, BVRI photometry
  86. GRB030429, refiend optical brightness
  87. GRB 030329: Optical limit (contemporaneous photography)
  88. GRB030418, BVRcIc field photometry
  89. GRB030429, BVRcIc field photometry
  90. GRB030429 (=H2695): A Long GRB Localized by the HETE WXM and SXC
  91. XRF030416 (=U10897): An X-Ray Flash Localized by the HETE WXM
  92. GRB030329: RTT150 optical observations and upper limit for a host
  93. GRB030501, optical observation
  94. GRB030501 triangulation (correction to GCN 2194)
  95. GRB030329: RTT150 optical observations and upper limit for a host
  96. GRB 030429: redshift from VLT spectroscopy
  97. GRB030501B triangulation (single error box)
  98. GRB 030329, BVRI photometry
  99. GRB030429: Optical Observations
  100. GRB030501: TAROT candidate afterglow present in archival images

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