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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"

24669 results found.

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

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