TY  - JOUR
A1  - Johnson, Michael D.
A1  - Akiyama, Kazunori
A1  - Blackburn, Lindy
A1  - Bouman, Katherine L.
A1  - Broderick, Avery E.
A1  - Cardoso, Vitor
A1  - Fender, Rob P.
A1  - Fromm, Christian M.
A1  - Galison, Peter
A1  - Gómez, José L.
A1  - Haggard, Daryl
A1  - Lister, Matthew L.
A1  - Lobanov, Andrei P.
A1  - Markoff, Sera
A1  - Narayan, Ramesh
A1  - Natarajan, Priyamvada
A1  - Nichols, Tiffany
A1  - Pesce, Dominic W.
A1  - Younsi, Ziri
A1  - Chael, Andrew
A1  - Chatterjee, Koushik
A1  - Chaves, Ryan
A1  - Doboszewski, Juliusz
A1  - Dodson, Richard
A1  - Doeleman, Sheperd S.
A1  - Elder, Jamee
A1  - Fitzpatrick, Garret
A1  - Haworth, Kari
A1  - Houston, Janice
A1  - Issaoun, Sara
A1  - Kovalev, Yuri Y.
A1  - Levis, Aviad
A1  - Lico, Rocco
A1  - Marcoci, Alexandru
A1  - Martens, Niels C. M.
A1  - Nagar, Neil M.
A1  - Oppenheimer, Aaron
A1  - Palumbo, Daniel C. M.
A1  - Ricarte, Angelo
A1  - Rioja, María  J.
A1  - Roelofs, Freek
A1  - Thresher, Ann C.
A1  - Tiede, Paul
A1  - Weintroub, Jonathan
A1  - Wielgus, Maciek
T1  - Key science goals for the next-generation Event Horizon Telescope
JF  - Galaxies
N2  - The Event Horizon Telescope (EHT) has led to the first images of a supermassive black hole, revealing the central compact objects in the elliptical galaxy M87 and the Milky Way. Proposed upgrades to this array through the next-generation EHT (ngEHT) program would sharply improve the angular resolution, dynamic range, and temporal coverage of the existing EHT observations. These improvements will uniquely enable a wealth of transformative new discoveries related to black hole science, extending from event-horizon-scale studies of strong gravity to studies of explosive transients to the cosmological growth and influence of supermassive black holes. Here, we present the key science goals for the ngEHT and their associated instrument requirements, both of which have been formulated through a multi-year international effort involving hundreds of scientists worldwide.
KW  - black holes
KW  - general relativity
KW  - interferometry
KW  - accretion
KW  - relativistic jets
KW  - very-long-baseline interferometry
KW  - EHT
KW  - ngEHT
Y1  - 2023
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-313525
SN  - 2075-4434
VL  - 11
IS  - 3
ER  - 
TY  - JOUR
A1  - Riyas, Moidu Jameela
A1  - Syed, Tajdarul Hassan
A1  - Kumar, Hrishikesh
A1  - Kuenzer, Claudia
T1  - Detecting and analyzing the evolution of subsidence due to coal fires in Jharia coalfield, India using Sentinel-1 SAR data
JF  - Remote Sensing
N2  - Public safety and socio-economic development of the Jharia coalfield (JCF) in India is critically dependent on precise monitoring and comprehensive understanding of coal fires, which have been burning underneath for more than a century. This study utilizes New-Small BAseline Subset (N-SBAS) technique to compute surface deformation time series for 2017–2020 to characterize the spatiotemporal dynamics of coal fires in JCF. The line-of-sight (LOS) surface deformation estimated from ascending and descending Sentinel-1 SAR data are subsequently decomposed to derive precise vertical subsidence estimates. The most prominent subsidence (~22 cm) is observed in Kusunda colliery. The subsidence regions also correspond well with the Landsat-8 based thermal anomaly map and field evidence. Subsequently, the vertical surface deformation time-series is analyzed to characterize temporal variations within the 9.5 km\(^2\) area of coal fires. Results reveal that nearly 10% of the coal fire area is newly formed, while 73% persisted throughout the study period. Vulnerability analyses performed in terms of the susceptibility of the population to land surface collapse demonstrate that Tisra, Chhatatanr, and Sijua are the most vulnerable towns. Our results provide critical information for developing early warning systems and remediation strategies.
KW  - coal fire
KW  - InSAR
KW  - subsidence
KW  - remote sensing
KW  - coal
KW  - interferometry
KW  - SBAS
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-236703
SN  - 2072-4292
VL  - 13
IS  - 8
ER  -