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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"

2676 results found.

  1. GRB030329: final R-band light curve by MASTER
  2. GRB030329, optical observation
  3. GRB 030329, BRI photometry
  4. Further AAVSO V,B,R observations of GRB030329
  5. GRB 030329: Additional Mt. Laguna Optical Observations
  6. GRB 030329: optical observations
  7. GRB 030329, optical photometry
  8. GRB030329 - Light curve flattening
  9. GRB030329 - near contemporaneous optical limits from CONCAM
  10. GRB030329, SPM optical observations
  11. GRB 030328 Optical Observations
  12. GRB030328: Decay index
  13. Possible GRB030323 localized by INTEGRAL
  14. IPN triangulation of GRB030325 (single small error box)
  15. IPN triangulation of GRB030325 (two small error boxes)
  16. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  17. GRB 030320: Optical Observations
  18. IPN triangulation of GRB030320 (small error box)
  19. GRB030227 localized by INTEGRAL
  20. GRB030131: Optical limits for corrected position
  21. GRB 030131: afterglow candidate
  22. GRB030131: Optical limit
  23. GRB030115: Optical Observations, Swiss Telescope at La Silla (ESO, Chile)
  24. GRB021211 (=H2493): A Bright, Long GRB Localized by HETE-2 in Near-Real Time
  25. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  26. IPN triangulation of GRB021027 (single large error box)
  27. GRB 021016, optical observations
  28. GRB021004: Optical Observations
  29. GRB021004: BVRc photometry
  30. GRB 021004: Optical observations at RIKEN
  31. GRB 021004: Optical Observations
  32. GRB 021004: Optical Observations
  33. GRB 021004, SPM optical observations
  34. GRB020903(=H2314): An X-Ray Flash Localized by HETE
  35. GRB020813(=H2262): A Long, Bright Burst Localized by HETE in Near-Real Time
  36. IPN triangulation of GRB020708
  37. IPN triangulation of GRB020708
  38. GRB 020625, optical observations
  39. GRB 020317 : KISO Optical Observations
  40. GRB 020305: Candidate optical afterglow
  41. GRB020305, optical observations
  42. GRB020305 (=H1939): Localization of a GRB by HETE
  43. IPN Upper Limits to a GRB Associated With SN2002ap
  44. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  45. GRB 011130: Optical Observations of Chandra Sources
  46. GRB011130 (XRF011130) Chandra Observations
  47. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  48. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  49. SGR1806-20: Localization by HETE
  50. GRB010222: possible optical counterpart
  51. IPN triangulation of GRB 001004
  52. GRB000926 K'-band Observation
  53. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  54. IPN localization of GRB000801
  55. IPN localization of GRB000730
  56. GRB000623
  57. GRB000615, R-band photometry
  58. BeppoSAX X-ray transient/possible GRB000608
  59. GRB 000408, optical observations
  60. IPN annulus for GRB000115
  61. Single IPN error box for GRB991229
  62. IPN error boxes for GRB991229
  63. Single IPN error box for GRB991221
  64. IPN error boxes for GRB991221
  65. GRB 991216 RXTE ASM Observations
  66. IPN localization of GRB990704
  67. GRB990510: X-ray afterglow
  68. GRB990510 optical observations
  69. GRB 990506, optical observations
  70. GRB 990506, optical observations
  71. GRB 981220 Optical observations
  72. GRB981226, sub-millimeter observations
  73. Optical Observations of GRB981226
  74. GRB 981220:Optical Observations
  75. GRB 981226 - Infrared Observations
  76. GRB 971214: USNOFS Observations Summary

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