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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"

26338 results found.

  1. Confirmation of IPN position for GRB001204
  2. IPN triangulation of GRB001204 (short/hard)
  3. GRB 001105, further optical observations
  4. GRB001120: Gunn-i observations
  5. GRB001120, optical observations
  6. WSRT 4.8 GHz observations of GRB001109
  7. IPN triangulation of GRB001120
  8. Optical/NIR observations of GRB001109
  9. GRB 001109: deep JHK upper limits
  10. GRB 001109 X-ray afterglow with BeppoSAX
  11. GRB001109, R-band optical observations
  12. BeppoSAX ALERT: GRB001109
  13. IPN TRIANGULATION OF GRB001105
  14. GRB 991208: HST Imaging of the Host Galaxy
  15. GRB000926: R-image of the host galaxy
  16. GRB 001025B, I-band observations
  17. XMM-Newton observation of GRB001025
  18. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  19. IPN triangulation of GRB001025
  20. ASM Localization of GRB 001025
  21. GRB001007, Radio observations
  22. IPN TRIANGULATION OF GRB001020
  23. GRB001019, Optical Observations
  24. GRB001018, Gamma Ray Observations
  25. IPN TRIANGULATION OF GRB001019
  26. IPN TRIANGULATION OF GRB001018
  27. IPN TRIANGULATION OF GRB 001017
  28. GRB 000926: Improved Absorber Redshift
  29. HETE positions added to GCN
  30. BeppoSAX ALERT: GRB001011
  31. GRB 001007, BVR-band observations
  32. GRB000926 - Amateur Optical Observations
  33. CONCAM null result on GRB001005
  34. IPN triangulation of GRB001007
  35. HETE-2 Launches Successfully
  36. IPN triangulation of GRB001005
  37. HETE-2 48 hour Launch Delay
  38. GRB 000926 Chandra Observation
  39. IPN triangulation of GRB 001004
  40. Public availability of BeppoSAX data of GRB000926
  41. GRB000926: X-ray afterglow by BeppoSAX: revised fluxes (fwd)
  42. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  43. GRB000926 - Optical observations
  44. GRB 000926, Optical Decay
  45. GRB000926 - Optical observations
  46. GRB000926 - Optical observations
  47. GRB 000926, Optical Observations
  48. GRB000926 - Optical observations
  49. GRB000911: optical VLT observations
  50. GRB000926 K'-band Observation
  51. GRB000926 optical observations
  52. GRB000926 - Optical observations
  53. Re: GRB 000926, optical observation by Oksanen (vsnet-grb)
  54. GRB 000926, optical observation by Oksanen (vsnet-grb)
  55. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  56. Spectroscopic Redshift of GRB 000926
  57. GRB000926, radio observations
  58. GRB 000926: Optical candidate
  59. Optical candidate for GRB000926
  60. IPN triangulation of GRB000926
  61. GRB 000911, BVRI field photometry
  62. IPN triangulation of GRB000925
  63. GRB000911, Radio and Optical observations
  64. IPN triangulation of GRB000911
  65. IPN triangulation of GRB000910
  66. GRB 000830: Optical observations
  67. GRB000210, Optical observations
  68. Chandra Position of GRB000210
  69. IPN triangulation of GRB000830
  70. HST/STIS observations of the host galaxy of GRB 980329
  71. IPN localization of GRB000820
  72. GRB000812, TNG R-band observations
  73. GRB000801 & GRB000730, Gamma Ray Observations
  74. GRB000730, Gamma Ray Observations
  75. IPN localization of GRB000812
  76. IPN localization of GRB000811
  77. GRB000801, Gamma Ray Observations
  78. GRB000301C, UBVI optical observations
  79. IPN localization of GRB000801
  80. IPN localization of GRB000730B
  81. IPN localization of GRB000730
  82. GRB 990510: Possible detection of a host galaxy
  83. IPN localization of GRB000727
  84. GRB 990712: Late time HST/STIS Observations
  85. GRB 991216, HST/STIS observations
  86. GRB981226, HST/STIS observations of the host galaxy
  87. GRB000630, optical observations
  88. GRB000630, Optical Observations
  89. GRB000630, optical observations
  90. GRB000630, optical observations
  91. GRB000630: Optical observations
  92. GRB000630, Radio Observations
  93. IPN triangulation of GRB000630
  94. GRB000418, HST/STIS Observations
  95. GRB 990506, HST/STIS Observations of the Host Galaxy
  96. GRB000623
  97. GRB000615: H-band observations
  98. IPN annulus for GRB000620
  99. GRB 000615: NIR further observations
  100. BeppoSAX ALERT: GRB000620

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