MEGARA-IFU detection of extended HeII4686 nebular emission in the central region of NGC1569 and its ionization budget
Y. D. Mayya, E. Carrasco, V. M. A. Gomez-Gonzalez, J. Zaragoza-Cardiel, A. Gil de Paz, P. A. Ovando, M. Sanchez-Cruces, L. Lomeli-Nunez, L. Rodriguez-Merino, D.… 展开作者
Y. D. Mayya, E. Carrasco, V. M. A. Gomez-Gonzalez, J. Zaragoza-Cardiel, A. Gil de Paz, P. A. Ovando, M. Sanchez-Cruces, L. Lomeli-Nunez, L. Rodriguez-Merino, D. Rosa-Gonzalez, S. Silich, G. Tenorio-Tagle, G. Bruzual, S. Charlot, R. Terlevich, E. Terlevich, O. Vega, J. Gallego, J. Iglesias-Paramo, A. Castillo-Morales, M. L. Garcia-Vargas, P. Gomez-Alvarez, S. Pascual, A. Perez-Calpena
We here report the detection of extended HeII4686 nebular emission in the central region of NGC1569 using the integral field spectrograph MEGARA at the 10.4-m Gran Telescopio Canarias. The observations cover a Field of View (FoV) of 12.5 arcsec x 11.3 arcsec at seeing-limited spatial resolution of ~15 pc and at a spectral resolution of R=6000 in the wavelength range 4330--5200 Angstrom. The emission extends over a semi-circular arc of ~40 pc width and ~150 pc diameter around the super star cluster A (SSC-A). The Av derived using Balmer decrement varies from the Galactic value of 1.6 mag to a maximum of ~4.5 mag, with a mean value of 2.65+/-0.60 mag. We infer 124+/-11 Wolf-Rayet (WR) stars in SSC-A using the HeII4686 broad feature and Av=2.3 mag. The He+ ionizing photon rate from these WR stars is sufficient to explain the luminosity of the HeII4686 nebula. The observationally-determined total He+ and H0 ionizing photon rates, their ratio, and the observed number of WR stars in SSC-A are all consistent with the predictions of simple stellar population models at an age of 4.0+/-0.5 Myr, and mass of (5.5+/-0.5)x10^5 Msun. Our observations reinforce the absence of WR stars in SSC-B, the second most massive cluster in the FoV. None of the other locations in our FoV where HeII4686 emission has been reported from narrow-band imaging observations contain WR stars.
The ionization structure and chemical history in isolated H ii regions of dwarf galaxies with VIMOS/IFU II. The Leo A galaxy
Universidad Andres Bello（安德烈斯贝略大学）；European Southern Observatory（欧洲南方天文台）；INAF – Osservatorio Astronomico di Trieste（意大利国家天体物理研究所的里雅斯特天文台）；INAF - Osservatorio Astronomico di Padova（意大利国家天体物理研究所帕多瓦天文台）
REBELS-IFU: Steeply rising star formation histories and the importance of dust obscuration in massive $z \simeq7$ galaxies revealed by multi-wavelength observations
Catching the Nebular Needle in a Polluted Haystack: Line-emission Signatures from Population III-forming Pockets around Massive Galaxies at the End of Reionization
University of Texas at Austin（德克萨斯大学奥斯汀分校）；Cosmic Frontier Center, The University of Texas at Austin（德克萨斯大学奥斯汀分校宇宙前沿中心）；Sapienza, Università di Roma（罗马第一大学）；INFN, Sezione di Roma I（意大利国家核物理研究所罗马第一分部）；INAF-Osservatorio Astronomico di Roma（意大利国家天体物理研究所罗马天文台）；Weinberg Institute for Theoretical Physics, University of Texas at Austin（德克萨斯大学奥斯汀分校温伯格理论物理研究所）
Chasing Cosmic Reionization: An Extremely Faint Highly Magnified Source at $z=5.66$ with high $ξ_{\rm ion}$
University of California, Los Angeles（加州大学洛杉矶分校）；INAF - OAS, Osservatorio di Astrofisica e Scienza dello Spazio di Bologna（意大利国家天体物理研究所-博洛尼亚天文与空间科学观测站）；Università degli Studi di Ferrara（费拉拉大学）；Università degli Studi di Milano（米兰大学）
Why is GN-z11 Bright, Compact, and Nitrogen Enhanced? Insights from UV Absorption and Emission Diagnostics
Institute for Cosmic Ray Research, The University of Tokyo（东京大学宇宙射线研究所）；Department of Physics, Graduate School of Science, The University of Tokyo（东京大学理学研究科物理学科）；National Astronomical Observatory of Japan（日本国立天文台）；Department of Astronomical Science, SOKENDAI (The Graduate University for Advanced Studies)（SOKENDAI（advanced studies）天文学系）；Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo（东京大学 Kavli 宇宙物理学与数学研究所）
The First Integral Field Unit Spectroscopic View of Shocked Cluster Galaxies
星系团通过与其他星系团的合并而成长，产生Mpc宽的冲击波，以1000-2500 km/s的速度穿过星系团内的介质。为了研究并合激波对星系团性质的影响，我们首次观测了位于低红移（z~0.2）、大质量（~2 $\times10^{15}$ M $_\odot$）、后核通道并合星系团CIZA J2242.8+5301（绰号"香肠“）激波锋面尾流中的5 H $α$发射星系的空间分辨光谱.我们的Gemini/GMOS-N积分场单元（IFU）观测，旨在捕捉H $α$和[NII]发射，揭示了星云气体分布，运动学和金属在星系超过16 kpc尺度。虽然星系显示出旋转支持的证据，但通量和速度图具有复杂的特征，如与星系团合并轴对齐的尾巴和气体流出。由于梯度与由内而外的星系盘生长不相容，金属丰度图与整个星系盘内外的持续恒星形成（SF）是一致的。结合以前的结果，这些试点观测提供了进一步的证据，集群合并和SF触发集群星系之间可能存在联系，这是一个潜在的基本发现，揭示了星系与环境的相互作用。
DREAMS. JWST Spectroscopy of a $z=8.3$ Galaxy with an ALMA Dust Continuum Detection: Early Dust, Very High $T_{\rm dust}$, and a Multi-wavelength [OIII] Ratio Discrepancy
Institute for Cosmic Ray Research, The University of Tokyo（宇宙射线研究所，东京大学）；Department of Physics, Graduate School of Science, The University of Tokyo（理学研究科物理学系，东京大学）；National Astronomical Observatory of Japan（日本国立天文台）；Astronomical Science Program, Graduate Institute for Advanced Studies, SOKENDAI（综合研究大学院大学天文学研究科，SOKENDAI）；Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU, WPI), The University of Tokyo（宇宙线起源研究宇宙前沿中心（Kavli IPMU），东京大学）；Institute of Liberal Arts and Science, Kanazawa University（金泽大学教养部）
