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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

32489 results found.

  1. GRB000926 : increasing optical decay slope
  2. GRB000926 optical observations
  3. GRB000926 - Optical observations
  4. Re: GRB 000926, optical observation by Oksanen (vsnet-grb)
  5. J and K band observations of GRB 000926
  6. GRB000911 Optical Observations
  7. GRB 000926: Lightcurve Update and Predictions
  8. GRB 000926, optical observation by Oksanen (vsnet-grb)
  9. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  10. GRB000926: Optical observations
  11. GRB 000926: Preliminary R-band Lightcurve
  12. GRB 000926 HST/Chandra TOO Status
  13. Spectroscopic Redshift of GRB 000926
  14. GRB 000926, Optical Observation
  15. GRB000926, radio observations
  16. GRB 000926: Optical candidate
  17. Optical candidate for GRB000926
  18. IPN triangulation of GRB000926
  19. GRB 000911, BVRI field photometry
  20. GRB000911: Corrected coordinates
  21. GRB000911: Sub-millimeter observations
  22. GRB000911: Optical Transient
  23. GRB000911, Radio and Optical observations
  24. GRB000911, Radio observations
  25. GRB000911: Optical observations
  26. False GRB alarm from RXTE/ASM on 8 Sept 2000
  27. GRB 000830: Optical observations
  28. GRB000830: Optical observations
  29. GRB000830, TNG B-band observations
  30. GRB000830: Optical observations
  31. GRB000210, Optical observations
  32. Chandra Position of GRB000210
  33. GRB000830: Optical observations
  34. HST/STIS observations of the host galaxy of GRB 980329
  35. HST/STIS observations of the chaotic environment of GRB 980613
  36. GRB000812, TNG R-band observations
  37. GRB000801 & GRB000730, Gamma Ray Observations
  38. GRB000812, Radio observations
  39. GRB000801, VLT-Antu R-band observations
  40. GRB000301C, UBVI optical observations
  41. GRB000801, Radio Observations
  42. GRB 991208 Host Galaxy Imaging
  43. Updated IPN coordinates for GRB000801
  44. IPN localization of GRB000801
  45. IPN localization of GRB000730B
  46. GRB 990510: Possible detection of a host galaxy
  47. GRB 990510 Host Galaxy Discovery
  48. GRB 000727, optical observations
  49. GRB 990705, HST/STIS observations of the host galaxy
  50. GRB 990712: Late time HST/STIS Observations
  51. GRB 991216, HST/STIS observations
  52. GRB000620, Radio Observations
  53. GRB981226, HST/STIS observations of the host galaxy
  54. GRB000630, optical observations
  55. GRB 000630: Detection of the Optical Afterglow
  56. GRB000630, Revised BVRI Field Photometry
  57. GRB000630, Optical Observations
  58. GRB000630, optical observations
  59. GRB000630, optical observations
  60. GRB000630, optical observations
  61. GRB000630, optical observations
  62. GRB000630: Optical observations
  63. GRB000630, Radio Observations
  64. possible optical counterpart of GRB 000630
  65. GRB 000623, optical observations
  66. GRB 000620, optical observations
  67. GRB000418, HST/STIS Observations
  68. GRB990123: Late-time HST/STIS observations of the host
  69. GRB 990506, HST/STIS Observations of the Host Galaxy
  70. GRB 000620: J-band observations
  71. GRB000620, optical observations
  72. GRB000615: H-band observations
  73. GRB990308, HST/STIS observations of the host galaxy
  74. GRB000620 - Optical observations
  75. GRB000620 Optical observations
  76. IPN annulus for GRB000620
  77. GRB000615, Radio observations
  78. GRB000607, optical observations
  79. GRB 000615: NIR further observations
  80. GRB990123, HST/STIS observations of the host galaxy
  81. GRB000616 optical observations
  82. GRB 000615, near-infrared observations
  83. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  84. GRB000615, further R-band photometry
  85. GRB 000615: NIR observations
  86. GRB000615, R-band photometry
  87. GRB980425, HST/STIS observations of the host galaxy
  88. The Hosts of GRB 980703 and GRB 971214
  89. GRB 000301C: Further Late-Time HST/STIS observations
  90. GRB000528: follow-up X-ray measurements and update of IPN annulus
  91. Optical Follow-up of GRB000529 Error Box
  92. GRB000607, Radio Observations
  93. GRB000604 optical non-detection
  94. GRB000604 - Optical observations
  95. GRB000604, optical observations
  96. GRB000528, optical observations at ESO
  97. GRB 000604 optical observations
  98. GRB 000418: Detection of the Host Galaxy
  99. GRB000604, optical observations, comparison with DPOSS
  100. GRB000528, Radio Observations

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