# Insights on bar quenching from a multi-wavelength analysis: The case of Messier 95

## TL;DR

This study investigates how the stellar bar in Messier 95 influences star formation suppression by redistributing gas, using multi-wavelength data to analyze stellar populations and gas content, revealing the bar's role in quenching star formation.

## Contribution

It provides new insights into the gas redistribution process by the stellar bar in Messier 95 and its impact on star formation suppression, based on comprehensive multi-wavelength analysis.

## Key findings

- The bar-region shows a UV flux cavity matching the bar length.
- Stellar populations in the bar are older (≥350 Myr) with a younger star-forming clump at the center (~150 Myr).
- The bar-region lacks neutral and molecular hydrogen, while the nucleus has abundant molecular gas.

## Abstract

The physical processes related to the effect of bar in the quenching of star formation in the region between the nuclear/central sub-kpc region and the ends of the bar (bar-region) of spiral galaxies is not fully understood. It is hypothesized that the bar can either stabilize the gas against collapse, inhibiting star formation or efficiently consume all the available gas, with no fuel for further star formation. We present a multi-wavelength study using the archival data of an early-type barred spiral galaxy, Messier 95, which shows signatures of suppressed star formation in the bar-region. Using the optical, ultraviolet, infrared, CO and HI imaging data we study the pattern of star formation progression, stellar/gas distribution and try to provide insights on the process responsible for the observed pattern. The FUV$-$NUV pixel colour map reveals a cavity devoid of UV flux in the bar-region that interestingly matches with the length of the bar ($\sim$ 4.2kpc). The central nuclear region of the galaxy is showing a blue color clump and along the major-axis of the stellar bar the colour progressively becomes redder. Based on a comparison to single stellar population models, we show that the region of galaxy along the major-axis of the bar (unlike the region outside the bar) is comprised of stellar populations with ages $\geq$ 350 Myr, with a star-forming clump in the center of younger ages ($\sim$ 150Myr). Interestingly the bar-region is also devoid of neutral and molecular hydrogen but with an abundant molecular hydrogen present at the nuclear region of the galaxy. Our results are consistent with a picture in which the stellar bar in Messier 95 is redistributing the gas by funneling gas inflows to nuclear region, thus making the bar-region devoid of fuel for star formation.