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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"

28040 results found.

  1. XRF 030723: Detection of a rebrightening in the optical afterglow
  2. XRF030723, BVRcIc field photometry update
  3. IPN triangulation of GRB030801 (large error box)
  4. GRB021206 optical counterpart upper limit
  5. IPN triangulation of GRB030726 (large error box)
  6. IPN triangulation of GRB030721 (large error box)
  7. XRF030723 Radio Observations
  8. XRF 030723: confirmation of fading optical counterpart
  9. XRF030723(=H2777): Chandra Observations
  10. GRB030723: Upper limits from historical observations
  11. XRF030723: Palomar observations and proposed counterpart
  12. GRB030725 (=H2779): A Bright GRB Localized by HETE
  13. XRF030723 (= H2777): Chandra Observations Scheduled
  14. XRF030723, BVRcIc field photometry correction
  15. XRF030723, ROTSE-III Early Observations
  16. XRF030723, BVRcIc field photometry
  17. XRF 030723, optical observations
  18. XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and
  19. Konus-Wind detection of the bursts from SGR1806-20 region
  20. SGR 1806-20, submm observations
  21. RXTE PCA Observations of SGR1806-20 Region
  22. IPN triangulation of GRB030714 (two large error boxes)
  23. IPN triangulation of GRB030715 (two large error boxes)
  24. GRB030706 triangulation (single large error box)
  25. GRB030329, optical observation in May
  26. IPN triangulation of GRB030626 (single large error box)
  27. IPN triangulation of GRB030626 (two large error boxes)
  28. GRB030329: second XMM-Newton observation
  29. GRB030329 -- RATAN-600 data in April-May
  30. GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
  31. IPN triangulation of GRB030606 (two alternate error boxes)
  32. GRB 030528: Infrared Observations and the Proposed IR Counterpart
  33. GRB 030528: tentative NIR counterpart
  34. GRB030528(=H2724): Observations with the Chandra X-ray Observatory
  35. GRB030528, BVRI field photometry
  36. GRB030329, SPM optical observations
  37. GRB030528: Chandra TOO Planned
  38. GRB030528(=H2724): Revised SXC Localization
  39. GRB 030528 Bisei optical observation
  40. GRB030528 (H2724): A long GRB localized by HETE
  41. GRB 030329: Correction to GCN 2254
  42. GRB 030329: Optical Observations
  43. GRB 030528 (=H2724) Kyoto optical observation
  44. GRB 030416: Optical Observations
  45. GRB 030329 Optical Observations
  46. GRB030329: XMM-Newton observation
  47. GRB 021004: HST observations
  48. GRB030324: Further Observations of the Candidate Optical Afterglow
  49. GRB030519B (=H2716): Peak Fluxes, Fluences, and Energy Spectrum
  50. IPN triangulation of GRB030519B=H2716 (small error box)
  51. HETE GRB030329, correction to Rc Observations in Loiano
  52. GRB 030329: Optical limit (contemporaneous imaging)
  53. IPN triangulation of GRB030509 (small errror box)
  54. GRB030329, BVRI photometry
  55. GRB030429, refiend optical brightness
  56. GRB 030329: Optical limit (contemporaneous photography)
  57. GRB030418, BVRcIc field photometry
  58. GRB030429, BVRcIc field photometry
  59. GRB030429 (=H2695): A Long GRB Localized by the HETE WXM and SXC
  60. XRF030416 (=U10897): An X-Ray Flash Localized by the HETE WXM
  61. GRB030329: RTT150 optical observations and upper limit for a host
  62. GRB030501, optical observation
  63. GRB030501 triangulation (correction to GCN 2194)
  64. GRB030329: RTT150 optical observations and upper limit for a host
  65. GRB 030429: redshift from VLT spectroscopy
  66. GRB030501B triangulation (single error box)
  67. GRB 030329, BVRI photometry
  68. GRB030429: Optical Observations
  69. GRB030501: TAROT candidate afterglow present in archival images
  70. GRB 030429: confirmation of afterglow candidate
  71. GRB 030329 Oprical observations in Rozhen observatory
  72. SNeIa AS THE POSSIBLE PROGENITORS OF SHORT-DURATION GRBs.
  73. IPN triangulation of GRB030425 (single error box)
  74. GRB 030329, the review of the sky area in plate archive (1950-1998)
  75. GRB 030329: optical spectropolarimetry at VLT
  76. GRB 030329: wide-field photograph by R. Tamura 1 hr after the burst
  77. GRB030329: optical polarization
  78. IPN triangulation of GRB030422 (two large error boxes)
  79. GRB030329, optical observation
  80. MASTER:optical observations GRB030418
  81. MASTER:optical observations probable GRB030414
  82. GRB030418: Kiso near infrared observations
  83. GRB 030418: Optical afterglow
  84. OT GRB 030329: early UBVRcIc spectral evolution
  85. OT GRB 030329: early spectrum
  86. IPN triangulation of GRB030414 (small error box)
  87. IPN triangulation of GRB030413 (small error box)
  88. Superluminal motion in GRB 030329 (Correction)
  89. Superluminal motion in GRB 030329
  90. GRB030329, optical position
  91. IPN triangulation of GRB030406 (small error box)
  92. IPN triangulation of GRB050403 (small error box)
  93. GRB 030329: BVRI photometry at Asiago
  94. GRB 030329: VLT V-band photometry
  95. Kiso observation of the GRB030329 at April 6
  96. GRB 030329, color evolution
  97. GRB030328, UBVRcIc field photometry
  98. GRB 030329 Optical observations
  99. GRB030329: Kiso B and R band observations
  100. GRB030328: R upper limit after 6 hours by MASTER

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