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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"

10761 results found.

  1. Clarification of GCN 2354 on SGR1806-20
  2. IPN detection of continued activity from SGR1806-20
  3. 030813 SGR event (Konus-Wind observation)
  4. SGR 1808-20 (=H2802): A Possible new SGR
  5. IPN triangulation of GRB030806 (large burst; large error box)
  6. IPN/HETE summary of recent bursts from SGR1806-20
  7. GRB030725, optical transient observations
  8. GRB030723: Upper limits from historical observations
  9. GRB030725, possible optical transient
  10. XRF030723, BVRcIc field photometry correction
  11. XRF030723, ROTSE-III Early Observations
  12. Konus-Wind detection of the bursts from SGR1806-20 region
  13. SGR 1806-20, submm observations
  14. H2768, H2770, and H2771: Three Bursts from SGR1806-20
  15. IPN triangulation of GRB030717 (annulus)
  16. RXTE PCA Observations of SGR1806-20 Region
  17. Triangulation of GRB030715 (single large error box)
  18. IPN triangulation of GRB030714 (two large error boxes)
  19. IPN triangulation of GRB030715 (two large error boxes)
  20. IPN detection of renewed activity from SGR1806-20
  21. IPN triangulation of GRB030629 (annulus)
  22. GRB030329: second XMM-Newton observation
  23. GRB030418: R optical observations
  24. HETE detection of burst from SGR1806-20
  25. GRB030329 -- RATAN-600 data in April-May
  26. GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
  27. IPN triangulation of GRB030606 (two alternate error boxes)
  28. GRB 030528: tentative NIR counterpart
  29. GRB030528(=H2724): Observations with the Chandra X-ray Observatory
  30. IPN triangulation of GRB030601 (annulus)
  31. GRB030329, SPM optical observations
  32. GRB 030329: optical observations
  33. GRB 030329/SN 2003dh: Jitter Episode
  34. GRB 030329: optical photometry at various french observatories
  35. GRB030329, Optical observations
  36. GRB 030329/SN 2003dh: Possible increase in brightness
  37. GRB030329: XMM-Newton observation
  38. GRB030429, refiend optical brightness
  39. GRB 030329: Optical limit (contemporaneous photography)
  40. GRB030501C triangulation (annulus)
  41. GRB 030329 Optical Observations
  42. GRB 030329, BVRI photometry
  43. GRB030429: Optical Observations
  44. GRB 030501: TAROT possible candidate counterpart
  45. GRB030429, possible optical counterpart
  46. GRB 030429: ROTSE-III observations
  47. GRB030329 observed as a sudden ionospheric disturbance (SID)
  48. SNeIa AS THE POSSIBLE PROGENITORS OF SHORT-DURATION GRBs.
  49. GRB 030329, the review of the sky area in plate archive (1950-1998)
  50. GRB030329, optical observation
  51. MASTER:optical observations GRB030418
  52. MASTER:optical observations probable GRB030414
  53. ROTSE-III prompt optical detections of GRB 030418
  54. GRB030329: VR Photometry at TNG
  55. IPN triangulation of GRB030413 (small error box)
  56. IPN triangulation of GRB030406 (small error box)
  57. GRB030329: BV photographic observations
  58. GRB030329: RTT150 optical observations
  59. GRB030329: Kiso B and R band observations
  60. GRB 030329: BV photographic observations
  61. GRB 030329, BVRI photometry
  62. GRB030329: final R-band light curve by MASTER
  63. GRB030329 - more 15 GHz radio data
  64. OT GRB light curves and SN predictions
  65. GRB 030329, BRI photometry
  66. GRB030328: Full Observation, X-ray Fading and Spectrum Measured
  67. Further AAVSO V,B,R observations of GRB030329
  68. GRB 030329: Additional Mt. Laguna Optical Observations
  69. GRB030329: further optical photometry and evidence for a light curve discontinuity
  70. GRB030329 - OT rebrightens
  71. AAVSO V & R observations of GRB030329
  72. GRB 030329: optical observations
  73. GRB030329 - Light curve flattening
  74. GRB030328: X-ray Fading and Spectrum Measured with Chandra
  75. GRB 030329: visual observations
  76. GRB030328: X-ray Afterglow Observed with Chandra
  77. GRB 030329, R-band observations, supplement
  78. GRB030329:optical observations by MASTER
  79. GRB030329 (=H2652): A Long, Extremely Bright GRB Localized by the HETE WXM and SXC
  80. RXTE detection of GRB 030329 afterglow
  81. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  82. GRB 030328: Finding chart
  83. GRB 030328: Optical afterglow candidate
  84. GRB030324, optical observations
  85. GRB030324, Optical Observations
  86. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  87. GRB 030324, optical observations
  88. IPN triangulation of GRB030317 (annulus)
  89. GRB 030227: Optical limit at RIKEN
  90. IPN triangulation of GRB030306 (single small error box)
  91. IPN triangulation of GRB030306 (two small error boxes)
  92. IPN triangulation of GRB030306 (intense; annulus only so far)
  93. GRB030226: Analysis of Chandra data
  94. GRB 030227: fading of candidate optical afterglow 'S1-A'
  95. GRB 030227, possible optical counterpart of XMM-Newton source
  96. GRB030227 - faint tentative OT candidate
  97. GRB 030227: Kyoto optical observation
  98. GRB030227 localized by INTEGRAL
  99. GRB 030226, optical observations
  100. GRB 030226 Optical Spectra and R,I,z' Imaging

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