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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"

25081 results found.

  1. XRF030416 (=U10897): An X-Ray Flash Localized by the HETE WXM
  2. GRB030329: RTT150 optical observations and upper limit for a host
  3. GRB030501, optical observation
  4. GRB030501 triangulation (correction to GCN 2194)
  5. GRB030329: RTT150 optical observations and upper limit for a host
  6. GRB 030429: redshift from VLT spectroscopy
  7. GRB030501B triangulation (single error box)
  8. GRB 030329, BVRI photometry
  9. GRB030429: Optical Observations
  10. GRB030501: TAROT candidate afterglow present in archival images
  11. GRB 030429: confirmation of afterglow candidate
  12. GRB 030329 Oprical observations in Rozhen observatory
  13. SNeIa AS THE POSSIBLE PROGENITORS OF SHORT-DURATION GRBs.
  14. IPN triangulation of GRB030425 (single error box)
  15. GRB 030329, the review of the sky area in plate archive (1950-1998)
  16. GRB 030329: optical spectropolarimetry at VLT
  17. GRB 030329: wide-field photograph by R. Tamura 1 hr after the burst
  18. GRB030329: optical polarization
  19. IPN triangulation of GRB030422 (two large error boxes)
  20. GRB030329, optical observation
  21. MASTER:optical observations GRB030418
  22. MASTER:optical observations probable GRB030414
  23. GRB030418: Kiso near infrared observations
  24. GRB 030418: Optical afterglow
  25. OT GRB 030329: early UBVRcIc spectral evolution
  26. OT GRB 030329: early spectrum
  27. IPN triangulation of GRB030414 (small error box)
  28. IPN triangulation of GRB030413 (small error box)
  29. Superluminal motion in GRB 030329 (Correction)
  30. Superluminal motion in GRB 030329
  31. GRB030329, optical position
  32. IPN triangulation of GRB030406 (small error box)
  33. IPN triangulation of GRB050403 (small error box)
  34. GRB 030329: BVRI photometry at Asiago
  35. GRB 030329: VLT V-band photometry
  36. Kiso observation of the GRB030329 at April 6
  37. GRB 030329, color evolution
  38. GRB030328, UBVRcIc field photometry
  39. GRB 030329 Optical observations
  40. GRB030329: Kiso B and R band observations
  41. GRB030328: R upper limit after 6 hours by MASTER
  42. SDSS 0.5m PT observations of GRB030329 (correction)
  43. SDSS 0.5m PT observations of GRB030329
  44. GRB030329: final R-band light curve by MASTER
  45. GRB030329, optical observation
  46. GRB030329, new UBVRcIc field photometry
  47. GRB 030329, light curve and SN prediction
  48. GRB 030329, BRI photometry
  49. GRB030328: Full Observation, X-ray Fading and Spectrum Measured
  50. GRB030329: Optical observations at Teramo
  51. GRB 030329: Radio observations at GMRT
  52. Further AAVSO V,B,R observations of GRB030329
  53. GRB 030329: Additional Mt. Laguna Optical Observations
  54. GRB 030329: Observations with ANDICAM
  55. GRB030329: further optical photometry and evidence for a light curve discontinuity
  56. triangulation of GRB 030331 (single error box)
  57. GRB 030329: optical observations
  58. Photometry of GRB030329 - Constant OT Magnitude
  59. GRB030329 - OT brightens
  60. GRB 030329, optical photometry
  61. GRB 030324: Optical and NIR Observations
  62. GRB030329: R band light curve by MASTER
  63. GRB030329 - Light curve flattening
  64. GRB 030324, optical search
  65. GRB 030329, optical observations
  66. GRB030328: X-ray Fading and Spectrum Measured with Chandra
  67. GRB030329a: detection by Konus-Wind
  68. GRB030329b: detection by Konus-Wind and Helicon-CoronasF
  69. GRB030329, BVRcIc field photometry
  70. GRB030329, SPM optical observations
  71. GRB 030329: Optical decay and synthesis
  72. GRB030329 optical observations
  73. GRB 030329: Optical pre-Imaging
  74. GRB 030329: Upper limit from 5.6 hours before trigger
  75. GRB030328: X-ray Afterglow Observed with Chandra
  76. GRB 030329, R-band observations
  77. GRB 030329: OT B and R photometry, decline rate
  78. GRB030329: Upper limits from recent and historical observations.
  79. GRB030329 (=H2652): A Long, Extremely Bright GRB Localized by the HETE WXM and SXC
  80. GRB 030329: Optical Afterglow Observations
  81. GRB 030328: optical observations
  82. GRB 030329: Optical afterglow fading
  83. GRB 030328: OT photometry
  84. GRB030328: optical spectroscopy at TNG
  85. GRB030328: optical photometry at the TNG
  86. VLT spectra of GRB 030328
  87. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  88. GRB 030328: Optical observations
  89. GRB030324 optical observation
  90. GRB030131, BVRcIc field photometry
  91. Possible GRB030323 localized by INTEGRAL
  92. GRB030323: Detection on 2003/03/24
  93. IPN triangulation of GRB030326 (single small error box)
  94. IPN triangulation of GRB030325 (two small error boxes)
  95. GRB030323: V, R, I photometry
  96. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  97. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  98. VLT/FORS2 spectra of GRB 030323
  99. GRB030323, optical observations
  100. GRB030324, BVRcIc field photometry

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