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Home , IC 1459, NGC 4522

2020 가을 학술대회

선속도 차이는 (308.8km/s)상승하였다. 이를 통해 성간 Chungnam National Nuniversity (CNU), 2Korea 물질의 물리량 차이만으로는 400km/s 이상의 큰 선속 Astronomy and Space Science Institute (KASI) 도 차이를 만드는 것은 어렵다. 관측에서 보이는 400km/s 이상의 몇몇 큰 선속도 차이의 은하를 위해서 We present the properties of in filaments 는 이 시뮬레이션에 포함되지 않은 성운 주위의 물질과 around the cluster with respect to their vertical 같은 부분이나, 은하 합병과 같은 극한의 상황이 필요할 distance from the filament spine. Using the 것이다. NASA-Sloan Atlas and group catalogs, we select galaxies that do not belong to groups in filaments. [포 GC-13] ALMA/ACA CO (1-0) observations The filament member galaxies are then defined as of group galaxies those located within 3.5 scale length from the filament spine. The filaments are mainly (~86%) 2 1 1 2 composed of low-mass dwarf galaxies of logh M Bumhyun Lee , Jing Wang , Aeree Chung , Luis C. ∗/M Ho1,3, Ran Wang1, Li Shao4, Tomonari Michiyama1, ⊙ < 9 dominantly located on the blue cloud in Shun Wang1,3, Eric W. Peng1,3, Virginia Kilborn5,6 color-magnitude diagrams. We observe that the g − 1 Kavli Institute for Astronomy and Astrophysics, r color and stellar mass of galaxies correlate with Peking University, China, 2Department of their vertical distance from the filament spine in Astronomy, Yonsei University, Korea, 3Department which the color becomes red and stellar mass of Astronomy, School of Physics, Peking decreases with increasing vertical filament distance. University, China, 4National Astronomical The galaxies were divided into two subsamples in Observatories, Chinese Academy of Sciences, different stellar mass ranges, with lower-mass 2 5 logh M China, Centre for Astrophysics and ( ∗/M⊙ ≤ 8) galaxies showing a clear negative logh2M Supercomputing, Swinburne University of g−r color gradient, whereas higher-mass ( ∗ Technology, Australia, 6ARC Centre of Excellence /M⊙ > 8) galaxies have a flat distribution against the for All Sky Astrophysics in 3 Dimensions (ASTRO vertical filament distance. We observe a negative 3D), Australia EW(Hα) gradient for higher-mass galaxies, whereas lower-mass galaxies show no distinct variation in groups are the place where many EW(Hα) against the vertical filament distance. In galaxies feel the impact of the surroundings (e.g., contrast, the NUV − r color distribution of merging, tidal interaction, stripping) higher-mass galaxies shows no strong dependence before joining bigger structures like (sub)clusters. on the vertical filament distance, whereas the A significant fraction of galaxies is quenched in the lower-mass galaxies show a distinct negative NUV group environment. Such “pre-processing” of − r color gradient. We do not witness clear gradients galaxies in groups is likely to affect galaxy of HI fraction in either the higher- or lower-mass evolution tremendously. To better understand how subsamples. We propose that the negative color and environmental processes in galaxy groups affect stellar mass gradients of galaxies can be explained by molecular gas, formation activity, and galaxy mass assembly from past galaxy mergers at different evolution, we carried out CO imaging observations vertical filament distances. In addition, galaxy of group galaxies, using the Atacama Compact interactions might be responsible for the contrasting Array (ALMA/ACA). We selected all the targets that features of EW(Hα) and NUV − r color distributions have been detected in the GEMS-HI survey for two between the higher- and lower-mass subsamples. groups, making the sample of 40 galaxies (18 The HI fraction distributions of the two subsamples galaxies in IC 1459 group and 22 galaxies in NGC suggest that ram-pressure stripping and gas 4636 group). Our ALMA/ACA observation is the accretion could be ignorable processes in the Virgo first CO imaging survey for two groups. In this filaments. work, we present CO images of group galaxies, together with their maps and HI [포 GC-15] Phas-space Analysis of Halos images. Our ACA CO data show the asymmetric around Large-scale Filamentary Structures distribution of molecular gas in some of our samples. We discuss the impact of the group Hannah Jhee1, Hyunmi Song2, Rory Smith3, Jihye environment on molecular gas and star formation Shin3, and Inkyu Park1 activity 1University of Seoul, 2Yonsei University, 3KASI

[포 GC-14] Properties of Galaxies in Cosmic It has been studied that galaxies evolve following Filaments around the a typical trajectory on the phase space under the influence of deep gravitational potential of galaxy Youngdae Lee1, Suk Kim1, Soo-Chang Rey1, Jiwon clusters. Similarly, the large-scale filaments could Chung2 also affect the evolution of galaxies before falling 1Department of Astronomy and Space Science, into the clusters. In this study, using a dark

64 / Bull. Kor. Astron. Soc. Vol. 45 No.1, Oct. 2020 포스터발표초록 matter-only cosmological simulation, N-Cluster from Wide-Field Survey Explorer survey Run, we explore the evolution of galaxies on the in combination with radio survey data, such as phase space drien by large-scale filaments. We FIRST and NVSS. Our goal is to find observational find that galaxies around the filaments form a evidence of jet-driven outflows, which is expected common trajectory on the phase space as well as to be present in young luminous quasars from the cluster galaxies do. We also examine how these theoretical studies. While 16 targets were observed trajectories change depending on various physical with F2, narrow emission lines ([O III] or Hα) were parameters such as galaxy mass, initial distance of detected in 7 targets. FWHM of the emission lines galaxies from large-scale filaments, and cluster (up to 2500 km/s) were remarkably broad mass. compared to ordinary quasars, revealing the presence of strong outflows. The black hole mass [포 GC-16] Deep polarization observations of estimated from Eddington limit ranges from ~108 a ram pressure stripped galaxy, NGC 4522 to 109 solar mass, indicating that the target quasars are likely to be progenitors of massive Woorak Choi1, Aeree Chung1, Chang-goo Kim2, galaxies. Finally, we present the comparisons Bumhyun Lee3 between the outflow velocity and the physical 1Department of Astronomy, Yonsei University, properties of radio jets derived from the VLA radio Seoul, South Korea imaging data, in order to investigate the physical 2Department of Astrophysical Sciences, Princeton connection between the ionized outflows and radio University, Princeton, USA jets. 3Kavli Institute for Astronomy and Astrophysics, Peking University, China [포 GC-18] Evolution of Star Formation Rate - Density Relation over Cosmic Time in a We present high-resolution, high-sensitivity Simulated Universe: the Observed Reversal continuum data of NGC 4522 observed at 3 cm Reproduced (X-band) and 10 cm (S-band) in full polarization mode using the JVLA. This observation has 2 - 4 Ho Seong Hwang1, Jihye Shin1, Hyunmi Song1,2 times better spatial resolution and 2 - 5 times 1Korea Astronomy and Space Science Institute, better sensitivity compared to previous continuum 2Yonsei University observations. NGC 4522 is a Virgo undergoing active ram pressure stripping. This We use the IllustrisTNG cosmological galaxy is particularly well known for the CO hydrodynamical simulation to study the evolution emission detected outside its stellar disk, some of of star formation rate (SFR)-density relation over which coincides with the extraplanar HI gas and cosmic time. We construct several samples of Halpha patches. The major goal of our JVLA galaxies at different from z=2.0 to z=0.0, observation is to leverage our understanding of the which have the same comoving number density. influence of the ram pressure on the general ISM The SFR of galaxies decreases with local density at field and multi-phase medium. By combining our z=0.0, but its dependence on local density becomes new deep radio continuum data and previous weaker with . At z≳1.0, the SFR of galaxies observations, we will investigate how the B-field increases with local density (reversal of the properties can be affected by the ram pressure, SFR-density relation), and its dependence becomes and what roles the B-field plays in the stripping stronger with redshift. This change of SFR-density process of the multi-phased ISM and in the star relation with redshift still remains even when fixing formation activity when the ram pressure is the stellar masses of galaxies. The dependence of present. SFR on the distance to a also shows a change with redshift in a way similar to the case [포 GC-17] Physical Connection between based on local density, but the reversal happens at Ionized Outflows and Radio jets in Young a higher redshift, z~1.5, in clusters. On the other Radio Quasars. hand, the molecular gas fraction always decreases with local density regardless of redshift at Seong Hyeon Hwang, Minjin Kim z=0.0-2.0 even though the dependence becomes Department of Astronomy and Atmospheric weaker when we fix the stellar mass. Our study Sciences, Kyungpook National University demonstrates that the observed reversal of the SFR-density relation at z≳1.0 can be successfully reproduced in cosmological simulations. Our We present NIR spectroscopic data of young results are consistent with the idea that massive, radio quasars obtained from Flamingos-2 (F2) at star-forming galaxies are strongly clustered at Gemini-South. The targets are originally selected high redshifts, forming larger structures. These

한국천문학회보 제45권 1호, 2020년 10월 / 65