Multi-Wavelength Observations of Nearby Starburst Galaxies

AbstractDo cycles of violent, intense, but short-lived bursts constitute a significant mode of global starformation in present-day galaxies? Such events can have a profound effect on galaxies, particularly those with shallowpotential wells, and observational measures of their prevalence inform our understanding of a wide range of issues ingalaxy evolution. I will highlight what we have learned about starbursts from multi-wavelength observations of galaxiesin the local volume on both galactic and smaller scales, and explore how connections with the study of the deaths ofmassive stars may further our understanding of open issues in galaxy evolution.

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Influence from cosmological uncertainties on galaxy number count at faint limit

Modern Physics Letters A ◽

10.1142/s0217732315501394 ◽

2015 ◽

Vol 30 (28) ◽

pp. 1550139

Author(s):

Keji Shen ◽

Qiang Zhang ◽

Xin-He Meng

Keyword(s):

Galaxy Evolution ◽

Number Density ◽

Number Count ◽

Density Prediction ◽

Evolution Pattern ◽

Wide Range ◽

Different Types ◽

Physical Cosmology ◽

Cosmology Observations ◽

Near Future

Counting galaxy number density with wide range sky surveys has been well adopted in researches focusing on revealing evolution pattern of different types of galaxies. As understood intuitively the astrophysics environment physics is intimately affected by cosmology priors with theoretical estimation or vice versa, or simply stating that the astrophysics effect couples the corresponding cosmology observations or the way backwards. In this paper, we try to quantify the influence on galaxy number density prediction at faint luminosity limit from the uncertainties in cosmology, and how much the uncertainties blur the detection of galaxy evolution, with the hope that this trying may indeed help for precise and physical cosmology study in near future or vice versa.

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Observational Constraints on Galaxy Evolution from Multi-Wavelength Surveys

Progress of Theoretical Physics Supplement ◽

10.1143/ptps.172.44 ◽

2008 ◽

Vol 172 ◽

pp. 44-48

Author(s):

Swara Ravindranath

Keyword(s):

Galaxy Evolution ◽

Observational Constraints ◽

Multi Wavelength

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Recurrent Novae — A Review

Acta Polytechnica CTU Proceedings ◽

10.14311/app.2015.02.0246 ◽

2015 ◽

Vol 2 (1) ◽

pp. 246-251 ◽

Cited By ~ 2

Author(s):

K. Mukai

Keyword(s):

Accretion Rate ◽

Current Understanding ◽

X Rays ◽

Symbiotic Star ◽

Classical Novae ◽

Extensive Data ◽

Star Evolution ◽

Wide Range ◽

Multi Wavelength ◽

Recurrent Nova

In recent years, recurrent nova eruptions are often observed very intensely in wide range of wavelengths from radio to optical to X-rays. Here I present selected highlights from recent multi-wavelength observations. The enigma of T Pyx is at the heart of this paper. While our current understanding of CV and symbiotic star evolution can explain why certain subset of recurrent novae have high accretion rate, that of T Pyx must be greatly elevated compared to the evolutionary mean. At the same time, we have extensive data to be able to estimate how the nova envelope was ejected in T Pyx, and it turns to be a rather complex tale. One suspects that envelope ejection in recurrent and classical novae in general is more complicated than the textbook descriptions. At the end of the review, I will speculate that these two may be connected.

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Evolution Through the Post-starburst Phase: Using Post-starburst Galaxies as Laboratories for Understanding the Processes that Drive Galaxy Evolution

Publications of the Astronomical Society of the Pacific ◽

10.1088/1538-3873/ac0a59 ◽

2021 ◽

Vol 133 (1025) ◽

pp. 072001

Author(s):

K. Decker French

Keyword(s):

Galaxy Evolution ◽

Starburst Galaxies

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In pursuit of giants

Astronomy and Astrophysics ◽

10.1051/0004-6361/202038405 ◽

2020 ◽

Vol 644 ◽

pp. A144

Author(s):

D. Donevski ◽

A. Lapi ◽

K. Małek ◽

D. Liu ◽

C. Gómez-Guijarro ◽

...

Keyword(s):

Star Formation ◽

Galaxy Evolution ◽

Galaxy Formation ◽

Main Sequence ◽

Stellar Mass ◽

Starburst Galaxies ◽

Analytical Models ◽

Physical Parameters ◽

Star Forming ◽

Galaxy Populations

The dust-to-stellar mass ratio (Mdust/M⋆) is a crucial, albeit poorly constrained, parameter for improving our understanding of the complex physical processes involved in the production of dust, metals, and stars in galaxy evolution. In this work, we explore trends of Mdust/M⋆ with different physical parameters and using observations of 300 massive dusty star-forming galaxies detected with ALMA up to z ≈ 5. Additionally, we interpret our findings with different models of dusty galaxy formation. We find that Mdust/M⋆ evolves with redshift, stellar mass, specific star formation rates, and integrated dust size, but that evolution is different for main-sequence galaxies than it is for starburst galaxies. In both galaxy populations, Mdust/M⋆ increases until z ∼ 2, followed by a roughly flat trend towards higher redshifts, suggesting efficient dust growth in the distant universe. We confirm that the inverse relation between Mdust/M⋆ and M⋆ holds up to z ≈ 5 and can be interpreted as an evolutionary transition from early to late starburst phases. We demonstrate that the Mdust/M⋆ in starbursts reflects the increase in molecular gas fraction with redshift and attains the highest values for sources with the most compact dusty star formation. State-of-the-art cosmological simulations that include self-consistent dust growth have the capacity to broadly reproduce the evolution of Mdust/M⋆ in main-sequence galaxies, but underestimating it in starbursts. The latter is found to be linked to lower gas-phase metallicities and longer dust-growth timescales relative to observations. The results of phenomenological models based on the main-sequence and starburst dichotomy as well as analytical models that include recipes for rapid metal enrichment are consistent with our observations. Therefore, our results strongly suggest that high Mdust/M⋆ is due to rapid dust grain growth in the metal-enriched interstellar medium. This work highlights the multi-fold benefits of using Mdust/M⋆ as a diagnostic tool for: (1) disentangling main-sequence and starburst galaxies up to z ∼ 5; (2) probing the evolutionary phase of massive objects; and (3) refining the treatment of the dust life cycle in simulations.

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The XXL Survey

Astronomy and Astrophysics ◽

10.1051/0004-6361/201834581 ◽

2019 ◽

Vol 625 ◽

pp. A111 ◽

Cited By ~ 2

Author(s):

Andrew Butler ◽

Minh Huynh ◽

Anna Kapińska ◽

Ivan Delvecchio ◽

Vernesa Smolčić ◽

...

Keyword(s):

Galaxy Evolution ◽

High Redshift ◽

Radio Galaxies ◽

Optical Data ◽

Scaling Relation ◽

Radio Luminosity ◽

Hot Gas ◽

Luminosity Functions ◽

Wide Range ◽

Luminosity Evolution

The evolution of the comoving kinetic luminosity densities (Ωkin) of the radio loud high-excitation radio galaxies (RL HERGs) and the low-excitation radio galaxies (LERGs) in the ultimate XMM extragalactic survey south (XXL-S) field is presented. The wide area and deep radio and optical data of XXL-S have allowed the construction of the radio luminosity functions (RLFs) of the RL HERGs and LERGs across a wide range in radio luminosity out to high redshift (z = 1.3). The LERG RLFs display weak evolution: Φ(z)∝(1 + z)0.67 ± 0.17 in the pure density evolution (PDE) case and Φ(z)∝(1 + z)0.84 ± 0.31 in the pure luminosity evolution (PLE) case. The RL HERG RLFs demonstrate stronger evolution than the LERGs: Φ(z)∝(1 + z)1.81 ± 0.15 for PDE and Φ(z)∝(1 + z)3.19 ± 0.29 for PLE. Using a scaling relation to convert the 1.4 GHz radio luminosities into kinetic luminosities, the evolution of Ωkin was calculated for the RL HERGs and LERGs and compared to the predictions from various simulations. The prediction for the evolution of radio mode feedback in the Semi-Analytic Galaxy Evolution (SAGE) model is consistent with the Ωkin evolution for all XXL-S RL AGN (all RL HERGs and LERGs), indicating that the kinetic luminosities of RL AGN may be able to balance the radiative cooling of the hot phase of the IGM. Simulations that predict the Ωkin evolution of LERG equivalent populations show similar slopes to the XXL-S LERG evolution, suggesting that observations of LERGs are well described by models of SMBHs that slowly accrete hot gas. On the other hand, models of RL HERG equivalent populations differ in their predictions. While LERGs dominate the kinetic luminosity output of RL AGN at all redshifts, the evolution of the RL HERGs in XXL-S is weaker compared to what other studies have found. This implies that radio mode feedback from RL HERGs is more prominent at lower redshifts than was previously thought.

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Milky Way analogues in MaNGA: multiparameter homogeneity and comparison to the Milky Way

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz3126 ◽

2019 ◽

Vol 491 (3) ◽

pp. 3672-3701 ◽

Cited By ~ 2

Author(s):

N Boardman ◽

G Zasowski ◽

A Seth ◽

J Newman ◽

B Andrews ◽

...

Keyword(s):

Galaxy Evolution ◽

Milky Way ◽

Central Star ◽

Stellar Kinematics ◽

Star Forming ◽

Wide Range ◽

The Galaxy ◽

Central Regions ◽

Galaxy Population ◽

Stellar Masses

ABSTRACT The Milky Way provides an ideal laboratory to test our understanding of galaxy evolution, owing to our ability to observe our Galaxy over fine scales. However, connecting the Galaxy to the wider galaxy population remains difficult, due to the challenges posed by our internal perspective and to the different observational techniques employed. Here, we present a sample of galaxies identified as Milky Way analogues on the basis of their stellar masses and bulge-to-total ratios, observed as part of the Mapping Nearby Galaxies at Apache Point Observatory survey. We analyse the galaxies in terms of their stellar kinematics and populations as well as their ionized gas contents. We find our sample to contain generally young stellar populations in their outskirts. However, we find a wide range of stellar ages in their central regions, and we detect central active galactic nucleus-like or composite-like activity in roughly half of the sample galaxies, with the other half consisting of galaxies with central star-forming emission or emission consistent with old stars. We measure gradients in gas metallicity and stellar metallicity that are generally flatter in physical units than those measured for the Milky Way; however, we find far better agreement with the Milky Way when scaling gradients by galaxies’ disc scale lengths. From this, we argue much of the discrepancy in metallicity gradients to be due to the relative compactness of the Milky Way, with differences in observing perspective also likely to be a factor.

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On the reductions of aerofoil-turbulence interaction noise through multi-wavelength leading edge serrations

Proceedings of the Institution of Mechanical Engineers Part G Journal of Aerospace Engineering ◽

10.1177/0954410020965747 ◽

2020 ◽

pp. 095441002096574

Author(s):

S Narayanan ◽

Sushil Kumar Singh

Keyword(s):

Noise Reduction ◽

Maximum Amplitude ◽

Leading Edge ◽

Emission Angle ◽

Broadband Noise ◽

Dual Wavelength ◽

Flat Plates ◽

Wide Range ◽

Multi Wavelength ◽

Reduction Characteristics

This paper provides an experimental study into the use of multi-wavelength sinusoidal leading edge ( LE) serrations for enhancing the aerofoil-broadband noise reductions. The noise reduction performances of multi-wavelength serration profiles introduced on a flat plate are compared against those generated by single-wavelength profiles when applied separately. The multi-wavelength leading edge serration is made in such a way that its maximum amplitude is kept same as that of each single-wavelength ones to be compared. The present study reveals that the dual-wavelength serrations provide higher noise reductions over a narrow band of frequencies as compared to single and triple wavelength ones. Further, it reveals that the noise reduction characteristics of dual-wavelength serrated airfoils are similar to the flat plates. It shows that the baseline plate generate higher noise radiations for all emission angles as compared to leading edge serrated plates, but the common feature among them is the downstream directivity. For the range of frequencies 0.9 to 5 kHz, the highest directivity is seen at an emission angle of 55° for the baseline, while it occurs at 75° for the serrated plates. The dual wavelength serrations generate lowest acoustic radiations as compared to single and triple ones for all the emission angles. Also, it is noticed that the radiation levels of the dual serrations decrease with increase in amplitude of the serration, which shows that the longer dual serrations generate lowest acoustic radiations. Thus, the present study illustrates that the dual wavelength leading edge serrations act as the best passively modified serration profiles for achieving the highest noise reductions over a wide range of frequencies as compared to single and triple wavelength ones.

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Constraining star formation timescales with molecular gas and young star clusters

Proceedings of the International Astronomical Union ◽

10.1017/s174392131900838x ◽

2019 ◽

Vol 15 (S352) ◽

pp. 350-352

Author(s):

Kathryn Grasha ◽

Daniela Calzetti

Keyword(s):

Star Formation ◽

Galaxy Evolution ◽

Star Clusters ◽

Young Star ◽

Molecular Gas ◽

Gas Reservoirs ◽

Multi Wavelength ◽

Predictive Theory ◽

Young Star Clusters ◽

Co Observations

AbstractStar formation provides insight into the physical processes that govern the transformation of gas into stars. A key missing piece in a predictive theory of star formation is the link between scales of individual stars and star clusters up to entire galaxies. LEGUS is now providing the information to test the overall organization and spatial evolution of star formation. We present our latest findings of using star clusters from LEGUS combined with ALMA CO observations to investigate the transition from molecular gas to star formation in local galaxies. This work paves the way for future JWST observations of the embedded phase of star formation, the last missing ingredient to connect young star clusters and their relation with gas reservoirs. Multi-wavelength studies of local galaxies and their stellar and gas components will help shed light on early phases of galaxy evolution and properties of the ISM at high-z.

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