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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"

28051 results found.

  1. GRB030329, optical position
  2. IPN triangulation of GRB030406 (small error box)
  3. IPN triangulation of GRB050403 (small error box)
  4. GRB 030329: BVRI photometry at Asiago
  5. GRB 030329: VLT V-band photometry
  6. Kiso observation of the GRB030329 at April 6
  7. GRB 030329, color evolution
  8. GRB030328, UBVRcIc field photometry
  9. GRB 030329 Optical observations
  10. GRB030329: Kiso B and R band observations
  11. GRB030328: R upper limit after 6 hours by MASTER
  12. SDSS 0.5m PT observations of GRB030329 (correction)
  13. SDSS 0.5m PT observations of GRB030329
  14. GRB030329: final R-band light curve by MASTER
  15. GRB030329, optical observation
  16. GRB030329, new UBVRcIc field photometry
  17. GRB 030329, light curve and SN prediction
  18. GRB 030329, BRI photometry
  19. GRB030328: Full Observation, X-ray Fading and Spectrum Measured
  20. GRB030329: Optical observations at Teramo
  21. GRB 030329: Radio observations at GMRT
  22. Further AAVSO V,B,R observations of GRB030329
  23. GRB 030329: Additional Mt. Laguna Optical Observations
  24. GRB 030329: Observations with ANDICAM
  25. GRB030329: further optical photometry and evidence for a light curve discontinuity
  26. triangulation of GRB 030331 (single error box)
  27. GRB 030329: optical observations
  28. Photometry of GRB030329 - Constant OT Magnitude
  29. GRB030329 - OT brightens
  30. GRB 030329, optical photometry
  31. GRB 030324: Optical and NIR Observations
  32. GRB030329: R band light curve by MASTER
  33. GRB030329 - Light curve flattening
  34. GRB 030324, optical search
  35. GRB 030329, optical observations
  36. GRB030328: X-ray Fading and Spectrum Measured with Chandra
  37. GRB030329a: detection by Konus-Wind
  38. GRB030329b: detection by Konus-Wind and Helicon-CoronasF
  39. GRB030329, BVRcIc field photometry
  40. GRB030329, SPM optical observations
  41. GRB 030329: Optical decay and synthesis
  42. GRB030329 optical observations
  43. GRB 030329: Optical pre-Imaging
  44. GRB 030329: Upper limit from 5.6 hours before trigger
  45. GRB030328: X-ray Afterglow Observed with Chandra
  46. GRB 030329, R-band observations
  47. GRB 030329: OT B and R photometry, decline rate
  48. GRB030329: Upper limits from recent and historical observations.
  49. GRB030329 (=H2652): A Long, Extremely Bright GRB Localized by the HETE WXM and SXC
  50. GRB 030329: Optical Afterglow Observations
  51. GRB 030328: optical observations
  52. GRB 030329: Optical afterglow fading
  53. GRB 030328: OT photometry
  54. GRB030328: optical spectroscopy at TNG
  55. GRB030328: optical photometry at the TNG
  56. VLT spectra of GRB 030328
  57. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  58. GRB 030328: Optical observations
  59. GRB030324 optical observation
  60. GRB030131, BVRcIc field photometry
  61. Possible GRB030323 localized by INTEGRAL
  62. GRB030323: Detection on 2003/03/24
  63. IPN triangulation of GRB030326 (single small error box)
  64. IPN triangulation of GRB030325 (two small error boxes)
  65. GRB030323: V, R, I photometry
  66. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  67. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  68. VLT/FORS2 spectra of GRB 030323
  69. GRB030323, optical observations
  70. GRB030324, BVRcIc field photometry
  71. GRB030323, BVRcIc field calibration
  72. IPN triangulation of GRB030320 (small error box)
  73. Possible GRB 030320 localized by INTEGRAL
  74. IPN triangulation of GRB030306 (single small error box - REVISED)
  75. IPN triangulation of GRB030306 (single small error box)
  76. IPN triangulation of GRB030306 (two small error boxes)
  77. GRB030226, BVRc observations
  78. Chandra detection of the X-ray afterglow of GRB 030226
  79. GRB030227: Kiso optical upper limit
  80. GRB030227, BVRcIc field photometry
  81. GRB030226, BVRcIc field calibration
  82. GRB 030228, optical observations
  83. GRB 030227: Confirmed Optical Afterglow (S1-A)
  84. GRB 030227: fading of candidate optical afterglow 'S1-A'
  85. GRB030227:Optical observations
  86. GRB 030227, possible optical counterpart of XMM-Newton source
  87. GRB030227 - faint tentative OT candidate
  88. GRB 030226, optical observations
  89. XMM-Newton observation of GRB030227
  90. GRB030227: Kiso optical observations
  91. GRB 030227: Kyoto optical observation
  92. GRB 030226, optical light curve
  93. GRB030227 localized by INTEGRAL
  94. GRB 030226 : Predicted light curve
  95. GRB030226: ESI spectroscopy
  96. GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
  97. GRB 030226 simultaneous optical observations
  98. GRB 030226, optical observations
  99. GRB030226: Optical decay index
  100. GRB 030226 Optical Spectra and R,I,z' Imaging

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