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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"

26336 results found.

  1. GRB 001105, further optical observations
  2. GRB001120: Gunn-i observations
  3. GRB001120, optical observations
  4. WSRT 4.8 GHz observations of GRB001109
  5. IPN triangulation of GRB001120
  6. Optical/NIR observations of GRB001109
  7. GRB 001109: deep JHK upper limits
  8. GRB 001109 X-ray afterglow with BeppoSAX
  9. GRB001109, R-band optical observations
  10. BeppoSAX ALERT: GRB001109
  11. IPN TRIANGULATION OF GRB001105
  12. GRB 991208: HST Imaging of the Host Galaxy
  13. GRB000926: R-image of the host galaxy
  14. GRB 001025B, I-band observations
  15. XMM-Newton observation of GRB001025
  16. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  17. IPN triangulation of GRB001025
  18. ASM Localization of GRB 001025
  19. GRB001007, Radio observations
  20. IPN TRIANGULATION OF GRB001020
  21. GRB001019, Optical Observations
  22. GRB001018, Gamma Ray Observations
  23. IPN TRIANGULATION OF GRB001019
  24. IPN TRIANGULATION OF GRB001018
  25. IPN TRIANGULATION OF GRB 001017
  26. GRB 000926: Improved Absorber Redshift
  27. HETE positions added to GCN
  28. BeppoSAX ALERT: GRB001011
  29. GRB 001007, BVR-band observations
  30. GRB000926 - Amateur Optical Observations
  31. CONCAM null result on GRB001005
  32. IPN triangulation of GRB001007
  33. HETE-2 Launches Successfully
  34. IPN triangulation of GRB001005
  35. HETE-2 48 hour Launch Delay
  36. GRB 000926 Chandra Observation
  37. IPN triangulation of GRB 001004
  38. Public availability of BeppoSAX data of GRB000926
  39. GRB000926: X-ray afterglow by BeppoSAX: revised fluxes (fwd)
  40. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  41. GRB000926 - Optical observations
  42. GRB 000926, Optical Decay
  43. GRB000926 - Optical observations
  44. GRB000926 - Optical observations
  45. GRB 000926, Optical Observations
  46. GRB000926 - Optical observations
  47. GRB000911: optical VLT observations
  48. GRB000926 K'-band Observation
  49. GRB000926 optical observations
  50. GRB000926 - Optical observations
  51. Re: GRB 000926, optical observation by Oksanen (vsnet-grb)
  52. GRB 000926, optical observation by Oksanen (vsnet-grb)
  53. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  54. Spectroscopic Redshift of GRB 000926
  55. GRB000926, radio observations
  56. GRB 000926: Optical candidate
  57. Optical candidate for GRB000926
  58. IPN triangulation of GRB000926
  59. GRB 000911, BVRI field photometry
  60. IPN triangulation of GRB000925
  61. GRB000911, Radio and Optical observations
  62. IPN triangulation of GRB000911
  63. IPN triangulation of GRB000910
  64. GRB 000830: Optical observations
  65. GRB000210, Optical observations
  66. Chandra Position of GRB000210
  67. IPN triangulation of GRB000830
  68. HST/STIS observations of the host galaxy of GRB 980329
  69. IPN localization of GRB000820
  70. GRB000812, TNG R-band observations
  71. GRB000801 & GRB000730, Gamma Ray Observations
  72. GRB000730, Gamma Ray Observations
  73. IPN localization of GRB000812
  74. IPN localization of GRB000811
  75. GRB000801, Gamma Ray Observations
  76. GRB000301C, UBVI optical observations
  77. IPN localization of GRB000801
  78. IPN localization of GRB000730B
  79. IPN localization of GRB000730
  80. GRB 990510: Possible detection of a host galaxy
  81. IPN localization of GRB000727
  82. GRB 990712: Late time HST/STIS Observations
  83. GRB 991216, HST/STIS observations
  84. GRB981226, HST/STIS observations of the host galaxy
  85. GRB000630, optical observations
  86. GRB000630, Optical Observations
  87. GRB000630, optical observations
  88. GRB000630, optical observations
  89. GRB000630: Optical observations
  90. GRB000630, Radio Observations
  91. IPN triangulation of GRB000630
  92. GRB000418, HST/STIS Observations
  93. GRB 990506, HST/STIS Observations of the Host Galaxy
  94. GRB000623
  95. GRB000615: H-band observations
  96. IPN annulus for GRB000620
  97. GRB 000615: NIR further observations
  98. BeppoSAX ALERT: GRB000620
  99. GRB000620: BeppoSAX Alert
  100. GRB990123, HST/STIS observations of the host galaxy

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