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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"

28060 results found.

  1. XRF030823 (=H2818): An X-Ray Flash Localized by the HETE WXM and SXC
  2. IPN triangulation of GRB030921 (large error box)
  3. IPN triangulation of GRB030919 (large error box)
  4. GRB030913: Subaru Optical Observations
  5. GRB 030913, optical candidate
  6. GRB 030913, BOOTES observations
  7. IPN triangulation of GRB030916 (possible short/hard GRB; large error box)
  8. GRB030913: wide field imaging (7 sq.deg) of the error box by MASTER
  9. XRF 020427: Gemini-South Spectroscopic Observations of the Host
  10. XRF030824: Optical observations
  11. IPN triangulation of GRB030903 (large error box)
  12. IPN triangulation of GRB030827 (large error box)
  13. GRB030823: optical observations
  14. GRB030823: optical observation at Tokyo Tech
  15. Lulin follow-up observations of GRB030823
  16. GRB 030821(=H2814): A Faint, Long GRB Localized by the HETE WXM and the IPN
  17. IPN detection of continued activity from SGR1806-20
  18. GRB 030817 = H2808 TAROT optical observations
  19. SGR 1808-20 (=H2802): A Possible new SGR
  20. XRF030723(=H2777): Chandra Fading X-ray Afterglow Confirmed
  21. XRF 030723: Detection of a rebrightening in the optical afterglow
  22. XRF030723, BVRcIc field photometry update
  23. IPN triangulation of GRB030801 (large error box)
  24. GRB021206 optical counterpart upper limit
  25. IPN triangulation of GRB030726 (large error box)
  26. IPN triangulation of GRB030721 (large error box)
  27. XRF030723 Radio Observations
  28. XRF 030723: confirmation of fading optical counterpart
  29. XRF030723(=H2777): Chandra Observations
  30. GRB030723: Upper limits from historical observations
  31. XRF030723: Palomar observations and proposed counterpart
  32. GRB030725 (=H2779): A Bright GRB Localized by HETE
  33. XRF030723 (= H2777): Chandra Observations Scheduled
  34. XRF030723, BVRcIc field photometry correction
  35. XRF030723, ROTSE-III Early Observations
  36. XRF030723, BVRcIc field photometry
  37. XRF 030723, optical observations
  38. XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and
  39. Konus-Wind detection of the bursts from SGR1806-20 region
  40. SGR 1806-20, submm observations
  41. RXTE PCA Observations of SGR1806-20 Region
  42. IPN triangulation of GRB030714 (two large error boxes)
  43. IPN triangulation of GRB030715 (two large error boxes)
  44. GRB030706 triangulation (single large error box)
  45. GRB030329, optical observation in May
  46. IPN triangulation of GRB030626 (single large error box)
  47. IPN triangulation of GRB030626 (two large error boxes)
  48. GRB030329: second XMM-Newton observation
  49. GRB030329 -- RATAN-600 data in April-May
  50. GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
  51. IPN triangulation of GRB030606 (two alternate error boxes)
  52. GRB 030528: Infrared Observations and the Proposed IR Counterpart
  53. GRB 030528: tentative NIR counterpart
  54. GRB030528(=H2724): Observations with the Chandra X-ray Observatory
  55. GRB030528, BVRI field photometry
  56. GRB030329, SPM optical observations
  57. GRB030528: Chandra TOO Planned
  58. GRB030528(=H2724): Revised SXC Localization
  59. GRB 030528 Bisei optical observation
  60. GRB030528 (H2724): A long GRB localized by HETE
  61. GRB 030329: Correction to GCN 2254
  62. GRB 030329: Optical Observations
  63. GRB 030528 (=H2724) Kyoto optical observation
  64. GRB 030416: Optical Observations
  65. GRB 030329 Optical Observations
  66. GRB030329: XMM-Newton observation
  67. GRB 021004: HST observations
  68. GRB030324: Further Observations of the Candidate Optical Afterglow
  69. GRB030519B (=H2716): Peak Fluxes, Fluences, and Energy Spectrum
  70. IPN triangulation of GRB030519B=H2716 (small error box)
  71. HETE GRB030329, correction to Rc Observations in Loiano
  72. GRB 030329: Optical limit (contemporaneous imaging)
  73. IPN triangulation of GRB030509 (small errror box)
  74. GRB030329, BVRI photometry
  75. GRB030429, refiend optical brightness
  76. GRB 030329: Optical limit (contemporaneous photography)
  77. GRB030418, BVRcIc field photometry
  78. GRB030429, BVRcIc field photometry
  79. GRB030429 (=H2695): A Long GRB Localized by the HETE WXM and SXC
  80. XRF030416 (=U10897): An X-Ray Flash Localized by the HETE WXM
  81. GRB030329: RTT150 optical observations and upper limit for a host
  82. GRB030501, optical observation
  83. GRB030501 triangulation (correction to GCN 2194)
  84. GRB030329: RTT150 optical observations and upper limit for a host
  85. GRB 030429: redshift from VLT spectroscopy
  86. GRB030501B triangulation (single error box)
  87. GRB 030329, BVRI photometry
  88. GRB030429: Optical Observations
  89. GRB030501: TAROT candidate afterglow present in archival images
  90. GRB 030429: confirmation of afterglow candidate
  91. GRB 030329 Oprical observations in Rozhen observatory
  92. SNeIa AS THE POSSIBLE PROGENITORS OF SHORT-DURATION GRBs.
  93. IPN triangulation of GRB030425 (single error box)
  94. GRB 030329, the review of the sky area in plate archive (1950-1998)
  95. GRB 030329: optical spectropolarimetry at VLT
  96. GRB 030329: wide-field photograph by R. Tamura 1 hr after the burst
  97. GRB030329: optical polarization
  98. IPN triangulation of GRB030422 (two large error boxes)
  99. GRB030329, optical observation
  100. MASTER:optical observations GRB030418

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