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Title: STAR FORMATION EFFICIENCY IN THE BARRED SPIRAL GALAXY NGC 4303

Abstract

We present new {sup 12}CO (J = 1 - 0) observations of the barred galaxy NGC 4303 using the Nobeyama 45 m telescope (NRO45) and the Combined Array for Research in Millimeter-wave Astronomy (CARMA). The H{alpha} images of barred spiral galaxies often show active star formation in spiral arms, but less so in bars. We quantify the difference by measuring star formation rate (SFR) and star formation efficiency (SFE) at a scale where local star formation is spatially resolved. Our CO map covers the central 2.'3 region of the galaxy; the combination of NRO45 and CARMA provides a high fidelity image, enabling accurate measurements of molecular gas surface density. We find that SFR and SFE are twice as high in the spiral arms as in the bar. We discuss this difference in the context of the Kennicutt-Schmidt (KS) law, which indicates a constant SFR at a given gas surface density. The KS law breaks down at our native resolution ({approx}250 pc), and substantial smoothing (to 500 pc) is necessary to reproduce the KS law, although with greater scatter.

Authors:
 [1]; ;  [2];  [3]
  1. Department of Astronomy, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)
  2. National Astronomical Observatory of Japan, Mitaka, Tokyo 181-8588 (Japan)
  3. Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794-3800 (United States)
Publication Date:
OSTI Identifier:
21464859
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 721; Journal Issue: 1; Other Information: DOI: 10.1088/0004-637X/721/1/383
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASTRONOMY; DENSITY; GALAXIES; MAPS; RESOLUTION; STARS; TELESCOPES; PHYSICAL PROPERTIES

Citation Formats

Momose, Rieko, Okumura, Sachiko K., Sawada, Tsuyoshi, and Koda, Jin, E-mail: momo.s.rieko@nao.ac.j, E-mail: sokumura@nro.nao.ac.j, E-mail: tsawada@alma.c, E-mail: Jin.Koda@stonybrook.ed. STAR FORMATION EFFICIENCY IN THE BARRED SPIRAL GALAXY NGC 4303. United States: N. p., 2010. Web. doi:10.1088/0004-637X/721/1/383.
Momose, Rieko, Okumura, Sachiko K., Sawada, Tsuyoshi, & Koda, Jin, E-mail: momo.s.rieko@nao.ac.j, E-mail: sokumura@nro.nao.ac.j, E-mail: tsawada@alma.c, E-mail: Jin.Koda@stonybrook.ed. STAR FORMATION EFFICIENCY IN THE BARRED SPIRAL GALAXY NGC 4303. United States. doi:10.1088/0004-637X/721/1/383.
Momose, Rieko, Okumura, Sachiko K., Sawada, Tsuyoshi, and Koda, Jin, E-mail: momo.s.rieko@nao.ac.j, E-mail: sokumura@nro.nao.ac.j, E-mail: tsawada@alma.c, E-mail: Jin.Koda@stonybrook.ed. 2010. "STAR FORMATION EFFICIENCY IN THE BARRED SPIRAL GALAXY NGC 4303". United States. doi:10.1088/0004-637X/721/1/383.
@article{osti_21464859,
title = {STAR FORMATION EFFICIENCY IN THE BARRED SPIRAL GALAXY NGC 4303},
author = {Momose, Rieko and Okumura, Sachiko K. and Sawada, Tsuyoshi and Koda, Jin, E-mail: momo.s.rieko@nao.ac.j, E-mail: sokumura@nro.nao.ac.j, E-mail: tsawada@alma.c, E-mail: Jin.Koda@stonybrook.ed},
abstractNote = {We present new {sup 12}CO (J = 1 - 0) observations of the barred galaxy NGC 4303 using the Nobeyama 45 m telescope (NRO45) and the Combined Array for Research in Millimeter-wave Astronomy (CARMA). The H{alpha} images of barred spiral galaxies often show active star formation in spiral arms, but less so in bars. We quantify the difference by measuring star formation rate (SFR) and star formation efficiency (SFE) at a scale where local star formation is spatially resolved. Our CO map covers the central 2.'3 region of the galaxy; the combination of NRO45 and CARMA provides a high fidelity image, enabling accurate measurements of molecular gas surface density. We find that SFR and SFE are twice as high in the spiral arms as in the bar. We discuss this difference in the context of the Kennicutt-Schmidt (KS) law, which indicates a constant SFR at a given gas surface density. The KS law breaks down at our native resolution ({approx}250 pc), and substantial smoothing (to 500 pc) is necessary to reproduce the KS law, although with greater scatter.},
doi = {10.1088/0004-637X/721/1/383},
journal = {Astrophysical Journal},
number = 1,
volume = 721,
place = {United States},
year = 2010,
month = 9
}
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