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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"

24626 results found.

  1. triangulation of GRB 030331 (single error box)
  2. GRB 030329: optical observations
  3. Photometry of GRB030329 - Constant OT Magnitude
  4. GRB030329 - OT brightens
  5. GRB 030329, optical photometry
  6. GRB 030324: Optical and NIR Observations
  7. GRB030329: R band light curve by MASTER
  8. GRB030329 - Light curve flattening
  9. GRB 030324, optical search
  10. GRB 030329, optical observations
  11. GRB030328: X-ray Fading and Spectrum Measured with Chandra
  12. GRB030329a: detection by Konus-Wind
  13. GRB030329b: detection by Konus-Wind and Helicon-CoronasF
  14. GRB030329, BVRcIc field photometry
  15. GRB030329, SPM optical observations
  16. GRB 030329: Optical decay and synthesis
  17. GRB030329 optical observations
  18. GRB 030329: Optical pre-Imaging
  19. GRB 030329: Upper limit from 5.6 hours before trigger
  20. GRB030328: X-ray Afterglow Observed with Chandra
  21. GRB 030329, R-band observations
  22. GRB 030329: OT B and R photometry, decline rate
  23. GRB030329: Upper limits from recent and historical observations.
  24. GRB030329 (=H2652): A Long, Extremely Bright GRB Localized by the HETE WXM and SXC
  25. GRB 030329: Optical Afterglow Observations
  26. GRB 030328: optical observations
  27. GRB 030329: Optical afterglow fading
  28. GRB 030328: OT photometry
  29. GRB030328: optical spectroscopy at TNG
  30. GRB030328: optical photometry at the TNG
  31. VLT spectra of GRB 030328
  32. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  33. GRB 030328: Optical observations
  34. GRB030324 optical observation
  35. GRB030131, BVRcIc field photometry
  36. Possible GRB030323 localized by INTEGRAL
  37. GRB030323: Detection on 2003/03/24
  38. IPN triangulation of GRB030326 (single small error box)
  39. IPN triangulation of GRB030325 (two small error boxes)
  40. GRB030323: V, R, I photometry
  41. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  42. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  43. VLT/FORS2 spectra of GRB 030323
  44. GRB030323, optical observations
  45. GRB030324, BVRcIc field photometry
  46. GRB030323, BVRcIc field calibration
  47. IPN triangulation of GRB030320 (small error box)
  48. Possible GRB 030320 localized by INTEGRAL
  49. IPN triangulation of GRB030306 (single small error box - REVISED)
  50. IPN triangulation of GRB030306 (single small error box)
  51. IPN triangulation of GRB030306 (two small error boxes)
  52. GRB030226, BVRc observations
  53. Chandra detection of the X-ray afterglow of GRB 030226
  54. GRB030227: Kiso optical upper limit
  55. GRB030227, BVRcIc field photometry
  56. GRB030226, BVRcIc field calibration
  57. GRB 030228, optical observations
  58. GRB 030227: Confirmed Optical Afterglow (S1-A)
  59. GRB 030227: fading of candidate optical afterglow 'S1-A'
  60. GRB030227:Optical observations
  61. GRB 030227, possible optical counterpart of XMM-Newton source
  62. GRB030227 - faint tentative OT candidate
  63. GRB 030226, optical observations
  64. XMM-Newton observation of GRB030227
  65. GRB030227: Kiso optical observations
  66. GRB 030227: Kyoto optical observation
  67. GRB 030226, optical light curve
  68. GRB030227 localized by INTEGRAL
  69. GRB 030226 : Predicted light curve
  70. GRB030226: ESI spectroscopy
  71. GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
  72. GRB 030226 simultaneous optical observations
  73. GRB 030226, optical observations
  74. GRB030226: Optical decay index
  75. GRB 030226 Optical Spectra and R,I,z' Imaging
  76. GRB: Non-Referencing of GCN Circulars.
  77. IPN triangulation of GRB030217 (small error box)
  78. GRB 030131: marginal optical detection
  79. GRB 030204: Optical Observations
  80. GRB030204 field photometry
  81. GRB020819: Kiso R and I band observations
  82. GRB030131: Candidate Optical Afterglow
  83. IPN triangulation of GRB030204 (small error box)
  84. GRB 030131, optical observations
  85. GRB 030131: afterglow candidate
  86. GRB 030115, late-time optical observations
  87. GRB030131: corrected INTEGRAL position
  88. GRB 020819: Host galaxy at Radio Position
  89. IPN triangulation of GRB030131
  90. GRB 030131 optical observations
  91. GRB 030131 optical observations
  92. A long GRB detected by INTEGRAL
  93. GRB030115: 1.2 mm upper limits with MAMBO @ IRAM 30m
  94. GRB 030115, simultaneous observations by BOOTES-1
  95. GRB 030115: IR observations with IRSF/SIRIUS
  96. IPN triangulation of GRB030115C (large error box)
  97. GRB030115, afterglow candidate
  98. GRB 021211: R-band observations at late-time
  99. GRB030115: Optical Observations, Swiss Telescope at La Silla (ESO, Chile)
  100. GRB 030115 : Possible IR counterpart

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