English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We investigate the relation between the star formation rate surface density(Sigma_SFR) and the mass surface density of gas (Sigma_gas) in NGC 5194.VIRUS-P integral field spectroscopy is used to measure H-alpha, H-beta[NII]6548,6584, and [SII]6717,6731 emission line fluxes for 735 regions ~170 pcin diameter, and derive extinction corrected Sigma_SFRs. HI 21cm and CO mapsare used to measure the HI and H_2 gas surface density for each region. Wepresent a new method for fitting the Star Formation Law (SFL), which includesthe intrinsic scatter in the relation as a free parameter, allows the inclusionof non-detections, and is free of the systematics involved in performing linearcorrelations over incomplete data in logarithmic space. We use the[SII]/H-alpha ratio to separate the H-alpha flux contribution from the diffuseionized gas (DIG). After removing the DIG, we measure a slope N=0.82+/-0.05,and an intrinsic scatter epsilon=0.43+/-0.02 dex for the molecular gas SFL. Wealso measure a typical depletion timescale tau~2 Gyr, in good agreement withBigiel et al. (2008). The HI density shows no correlation with the SFR, and thetotal gas SFL closely follows the molecular gas SFL. We assess the validity ofcorrections applied in narrow-band H-alpha measurements to overcome issuesrelated to continuum subtraction, underlying photospheric absorption, andcontamination by the [NII] doublet. The disagreement with the super-linearmolecular SFL measured by Kennicutt et al. (2007) is due to differences in thefitting method. Our results support a low and close to constant star formationefficiency (SFE = 1/tau) in the molecular ISM. The data shows excellentagreement with the model of Krumholz et al (2009). The large intrinsic scattermay imply the existence of other important parameters setting the SFR.

The Spatially Resolved Star Formation Law from Integral Field Spectroscopy: VIRUS-P Observations of NGC 5194