Development of new imaging tehchnique for sub-mm VLBI

2014 Fiscal Year Final Research Report

• Project/Area Number: 24540242
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Astronomy
• Research Institution: National Astronomical Observatory of Japan
• Principal Investigator: HONMA Mareki 国立天文台, 水沢VLBI観測所, 教授 (20332166)
• Co-Investigator(Renkei-kenkyūsha): NAGAI Hiroshi 国立天文台, チリ観測所, 特任准教授 (00455198) ; OYAMA Tomoaki 国立天文台, 水沢VLBI観測所, 専門研究職員 (70425403) ; KAWABE Ryohei 国立天文台, 電波研究部, 教授 (10195141)
• Research Collaborator: AKIYAMA Kazunori ; TAZAKI Fumie ; HADA Kazuhiro
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: ブラックホール / 活動銀河中心核 / 電波天文学 / 超長基線電波干渉計 / サブミリ波

Outline of Final Research Achievements

In order to realize imaging with sub-mm VLBI using visibility phase information, we have explored imaging technique based on simulation data as well as real observational data of mm-VLBI. The methods we have considered include model fitting with least-square method, model estimation with Markov Chain Monte Carlo method, compressive sensing and so on. We have applied these methods to the real data of mm-VLBI observations, and for the first time successfully detected the radio core of M87 at 1 mm with a size of 5.5 Schwarzschild radii and also closure phase information on M87, which leaded us one step closer to the direct imaging of black hole shadows with sub-mm VLBI.

Free Research Field

ブラックホール天文学