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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"

28050 results found.

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

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