The failure of stellar feedback, magnetic fields, conduction, and morphological quenching in maintaining red galaxies

ABSTRACT The quenching ‘maintenance’ and related ‘cooling flow’ problems are important in galaxies from Milky Way mass through clusters. We investigate this in haloes with masses ∼$10^{12}\!-\!10^{14}\, {\rm M}_{\odot }$, using non-cosmological high-resolution hydrodynamic simulations with the FIRE-2 (Feedback In Realistic Environments) stellar feedback model. We specifically focus on physics present without AGN, and show that various proposed ‘non-AGN’ solution mechanisms in the literature, including Type Ia supernovae, shocked AGB winds, other forms of stellar feedback (e.g. cosmic rays), magnetic fields, Spitzer–Braginskii conduction, or ‘morphological quenching’ do not halt or substantially reduce cooling flows nor maintain ‘quenched’ galaxies in this mass range. We show that stellar feedback (including cosmic rays from SNe) alters the balance of cold/warm gas and the rate at which the cooled gas within the galaxy turns into stars, but not the net baryonic inflow. If anything, outflowing metals and dense gas promote additional cooling. Conduction is important only in the most massive haloes, as expected, but even at ∼$10^{14}\, {\rm M}_{\odot }$ reduces inflow only by a factor ∼2 (owing to saturation effects and anisotropic suppression). Changing the morphology of the galaxies only slightly alters their Toomre-Q parameter, and has no effect on cooling (as expected), so has essentially no effect on cooling flows or maintaining quenching. This all supports the idea that additional physics, e.g. AGN feedback, must be important in massive galaxies.

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Late Light Curves of Type Ia SNe

International Astronomical Union Colloquium ◽

10.1017/s0252921100009167 ◽

2005 ◽

Vol 192 ◽

pp. 183-188

Author(s):

Peter A. Milne ◽

G.Grant Williams

Keyword(s):

Magnetic Fields ◽

Energy Deposition ◽

Light Curves ◽

Current Status ◽

Type Ia Supernovae ◽

Type Ia ◽

Ia Supernovae

SummaryAt late times, the energy deposition in the ejecta of type Ia supernovae is dominated by the slowing of energetic positrons produced in 56Co → 56Fe decays. Through comparisons of simulations of energy deposition in SN Ia models with observed light curves from supernovae, we study the positron transport and thus the magnetic fields of SNe Ia. In this paper, we summarize the current status of these investigations, emphasizing the observations made of two recent SNe Ia, 1999by and 2000cx.

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Statistics of Radio-X-Ray Emission and Magnetic Fields in the Intergalactic Medium

Symposium - International Astronomical Union ◽

10.1017/s0074180900241168 ◽

1990 ◽

Vol 139 ◽

pp. 414-415

Author(s):

Hitoshi Hanami

Keyword(s):

Magnetic Field ◽

Cosmic Rays ◽

Magnetic Fields ◽

Intergalactic Medium ◽

Relativistic Electrons ◽

X Ray ◽

Cooling Flows ◽

Hot Plasma ◽

Inverse Compton ◽

The Magnetic Field

X-ray observations have demonstrated that the intergalactic medium in many clusters (cf. Coma, Perseus) contains a thin, hot plasma that may be produced by the accretion process in the gravitational potential of clusters with radiative cooling; this is usually called “cooling flows” (Fabian, Nulsen, and Canizares 1984; Sarazin 1986). On the other hand, the existence of radio halos in some clusters has been reported (Coma: Jaffe, Perola, and Valentijn 1976; A401: Roland et al. 1981). In addition, many elliptical galaxies in the center of clusters are also strong synchrotron radio sources. These radio emissions provide evidence for large amounts of relativistic electrons associated with the active phenomena in or around these galaxies and clusters. We can estimate the values or limits on the magnetic field in the cluster from the limits on the inverse Compton X-ray emission with the synchrotron radio emission (cf. Jaffe 1980). The intracluster field strength Bo is roughly 1 μG. It has been suggested that the influence of cosmic rays and magnetic fields is important for the properties and dynamics of the intercluster medium (Böhringer and Morfill 1988; Soker and Sarazin 1989). If cooling flows are real, this inward flow can impede the escape of the cosmic rays from the central galaxies in clusters and enhance the magnetic field. The confinement of the cosmic rays and the magnetic field in the center of clusters affects the gas of the intracluster medium.

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Constraints on environs around SN 2011fe and SN 2014J from radio modeling and observations

Proceedings of the International Astronomical Union ◽

10.1017/s1743921317005300 ◽

2017 ◽

Vol 12 (S331) ◽

pp. 69-74

Author(s):

Esha Kundu ◽

Peter Lundqvist ◽

Miguel A. Pérez-Torres

Keyword(s):

Magnetic Fields ◽

Loss Rate ◽

Particle Density ◽

Mass Loss Rate ◽

Upper Limit ◽

Electric And Magnetic Fields ◽

Type Ia ◽

Post Shock ◽

Ia Supernovae ◽

Shock Fronts

AbstractThe radio non-detection of two Type Ia supernovae (SNe) SN 2011fe and SN 2014J has been modeled considering synchrotron radiation from shock accelerated electrons in the SN shock fronts. With 10% each of the bulk kinetic energy in electric and magnetic fields, a very low density of the medium around both the SNe has been estimated from the null detection of radio emission, around 1 and 4 years after the explosion of SNe 2014J and 2011fe, respectively. Keeping the fraction of energy in electrons fixed at 10%, a medium with particle density ~ 1cm−3 is found when 1% of the post shock energy is in magnetic fields. In case of a wind medium, the former predicts the mass loss rate Ṁ to be <10−9M⊙ yr−1, and the latter gives an upper limit ~10−9M⊙ yr−1, for wind velocity of 100 kms−1, for both the SNe. The tenuous media obtained from this study favor the double degenerate as well as a spin up/down model for both SNe 2011fe and 2014J.

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Type Ia supernovae from non-accreting progenitors

Astronomy and Astrophysics ◽

10.1051/0004-6361/201936991 ◽

2020 ◽

Vol 635 ◽

pp. A72 ◽

Cited By ~ 1

Author(s):

J. Antoniadis ◽

S. Chanlaridis ◽

G. Gräfener ◽

N. Langer

Keyword(s):

Nuclear Energy ◽

Mass Range ◽

Type Ia Supernovae ◽

Core Collapse ◽

Star Forming ◽

Helium Stars ◽

Type Ia ◽

Complete Disruption ◽

Ia Supernovae ◽

Thermonuclear Runaway

Type Ia supernovae (SNe Ia) are manifestations of stars that are deficient in hydrogen and helium, and disrupt in a thermonuclear runaway. While explosions of carbon-oxygen white dwarfs are thought to account for the majority of events, part of the observed diversity may be due to varied progenitor channels. We demonstrate that helium stars with masses between ∼1.8 and 2.5 M⊙ may evolve into highly degenerate cores with near-Chandrasekhar mass and helium-free envelopes that subsequently ignite carbon and oxygen explosively at densities of ∼(1.8−5.9) × 109 g cm−3. This occurs either due to core growth from shell burning (when the core has a hybrid CO/NeO composition), or following ignition of residual carbon triggered by exothermic electron captures on 24Mg (for a NeOMg-dominated composition). We argue that the resulting thermonuclear runaway is likely to prevent core collapse, leading to the complete disruption of the star. The available nuclear energy at the onset of explosive oxygen burning suffices to create ejecta with a kinetic energy of ∼1051 erg, as in typical SNe Ia. Conversely, if these runaways result in partial disruptions, the corresponding transients would resemble SN Iax events similar to SN 2002cx. If helium stars in this mass range indeed explode as SNe Ia, then the frequency of events would be comparable to the observed SN Ib/c rates, thereby sufficing to account for the majority of SNe Ia in star-forming galaxies.

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The formation of the Milky Way halo and its dwarf satellites; a NLTE-1D abundance analysis

Astronomy and Astrophysics ◽

10.1051/0004-6361/201731582 ◽

2017 ◽

Vol 608 ◽

pp. A89 ◽

Cited By ~ 20

Author(s):

L. Mashonkina ◽

P. Jablonka ◽

T. Sitnova ◽

Yu. Pakhomov ◽

P. North

Keyword(s):

Milky Way ◽

Dwarf Galaxy ◽

Chemical Species ◽

Dwarf Spheroidal Galaxies ◽

Massive Galaxies ◽

Type Ia ◽

Ursa Minor ◽

R Process ◽

Ia Supernovae ◽

Process Elements

We present the non-local thermodynamic equilibrium (NLTE) abundances of up to 10 chemical species in a sample of 59 very metal-poor (VMP, −4 ≤ [Fe/H] ≾−2) stars in seven dwarf spheroidal galaxies (dSphs) and in the Milky Way (MW) halo. Our results are based on high-resolution spectroscopic datasets and homogeneous and accurate atmospheric parameters determined in Paper I. We show that once the NLTE effects are properly taken into account, all massive galaxies in our sample, that is, the MW halo and the classical dSphs Sculptor, Ursa Minor, Sextans, and Fornax, reveal a similar plateau at [α/Fe] ≃ 0.3 for each of the α-process elements: Mg, Ca, and Ti. We put on a firm ground the evidence for a decline in α/Fe with increasing metallicity in the Boötes I ultra-faint dwarf galaxy (UFD), that is most probably due to the ejecta of type Ia supernovae. For Na/Fe, Na/Mg, and Al/Mg, the MW halo and all dSphs reveal indistinguishable trends with metallicity, suggesting that the processes of Na and Al synthesis are identical in all systems, independent of their mass. The dichotomy in the [Sr/Ba] versus [Ba/H] diagram is observed in the classical dSphs, similarly to the MW halo, calling for two different nucleosynthesis channels for Sr. We show that Sr in the massive galaxies is well correlated with Mg suggesting a strong link to massive stars and that its origin is essentially independent of Ba, for most of the [Ba/H] range. Our three UFDs, that is Boötes I, UMa II, and Leo IV, are depleted in Sr and Ba relative to Fe and Mg, with very similar ratios of [Sr/Mg] ≃−1.3 and [Ba/Mg] ≃−1 on the entire range of their Mg abundances. The subsolar Sr/Ba ratios of Boötes I and UMa II indicate a common r-process origin of their neutron-capture elements. Sculptor remains the classical dSph, in which the evidence for inhomogeneous mixing in the early evolution stage, at [Fe/H] <−2, is the strongest.

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The dichotomy of dark matter fraction and total mass density slope of galaxies over five dex in mass

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz2320 ◽

2019 ◽

Vol 489 (4) ◽

pp. 5483-5493 ◽

Cited By ~ 5

Author(s):

C Tortora ◽

L Posti ◽

L V E Koopmans ◽

N R Napolitano

Keyword(s):

Dark Matter ◽

Mass Density ◽

Mass Range ◽

Elliptical Galaxies ◽

Galaxy Mergers ◽

Density Profiles ◽

Massive Galaxies ◽

Stellar Feedback ◽

Wide Range ◽

Low Mass

AbstractWe analyse the mass density distribution in the centres of galaxies across five orders of magnitude in mass range. Using high-quality spiral galaxy rotation curves and infrared photometry from SPARC, we conduct a systematic study of their central dark matter (DM) fraction (fDM) and their mass density slope (α), within their effective radius. We show that lower mass spiral galaxies are more DM dominated and have more shallow mass density slopes when compared with more massive galaxies, which have density profiles closer to isothermal. Low-mass (${M_{*}}\lesssim 10^{10}\, {\mathrm{M}_\odot}$) gas-rich spirals span a wide range of fDM values, but systematically lower than in gas-poor systems of similar mass. With increasing galaxy mass, the values of fDM decrease and the density profiles steepen. In the most massive late-type gas-poor galaxies, a possible flattening of these trends is observed. When comparing these results to massive (${M_{*}}\gtrsim 10^{10}\, {\mathrm{M}_\odot}$) elliptical galaxies from SPIDER and to dwarf ellipticals (dEs) from SMACKED, these trends result to be inverted. Hence, the values of both fDM and α, as a function of M*, exhibit a U-shape trend. At a fixed stellar mass, the mass density profiles in dEs are steeper than in spirals. These trends can be understood by stellar feedback from a more prolonged star formation period in spirals, causing a transformation of the initial steep density cusp to a more shallow profile via differential feedback efficiency by supernovae, and by galaxy mergers or AGN feedback in higher mass galaxies.

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The intermediate nebular phase of SN 2014J: onset of clumping as the source of recombination

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa839 ◽

2020 ◽

Vol 494 (2) ◽

pp. 2809-2822

Author(s):

P A Mazzali ◽

I Bikmaev ◽

R Sunyaev ◽

C Ashall ◽

S Prentice ◽

...

Keyword(s):

Magnetic Fields ◽

Intermediate Phase ◽

Phase 1 ◽

Emission Lines ◽

Type Ia Supernovae ◽

Progressive Decline ◽

Type Ia ◽

Local Magnetic Fields ◽

One Year ◽

Ia Supernovae

ABSTRACT At the age of about 1 yr, the spectra of most Type Ia supernovae (SNe Ia) are dominated by strong forbidden nebular emission lines of Fe ii and Fe iii. Later observations (at about 2 yr) of the nearby SN 2011fe showed an unexpected shift of ionization to Fe i and Fe ii. Spectra of the very nearby SN Ia 2014J at an intermediate phase (1–1.5 yr) that are presented here show a progressive decline of Fe iii emission, while Fe i is not yet strong. The decrease in ionization can be explained if the degree of clumping in the ejecta increases significantly at ∼1.5 yr, at least in the Fe-dominated zone. Models suggest that clumps remain coherent after about one year, behaving like shrapnel. The high density in the clumps, combined with the decreasing heating rate, would then cause recombination. These data may witness the phase of transition from relatively smooth ejecta to the very clumpy morphology that is typical of SN remnants. The origin of the increased clumping may be the development of local magnetic fields.

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A Single Degenerate Model for Ultra Super-Chandrasekhar Mass Progenitors of Type Ia Supernovae – Young and Low Metallicity Environments –

Proceedings of the International Astronomical Union ◽

10.1017/s1743921312014731 ◽

2011 ◽

Vol 7 (S281) ◽

pp. 76-79

Author(s):

Izumi Hachisu ◽

Mariko Kato ◽

Hideyuki Saio ◽

Ken'ichi Nomoto

Keyword(s):

Mass Range ◽

Type Ia Supernovae ◽

Mass Limit ◽

High Luminosity ◽

Lower Mass ◽

Initial Value ◽

Type Ia ◽

Low Metallicity ◽

Ia Supernovae ◽

Characteristic Mass

AbstractSome Type Ia supernovae (SNe Ia) are suggested to have progenitor white dwarfs (WDs) with mass of up to 2.4–2.8 M⊙, highly exceeding the Chandrasekhar mass limit. We present a new single degenerate (SD) model for SNe Ia progenitors, in which the WD mass can increase by accretion up to 2.3 (2.7) M⊙ from the initial value of 1.1 (1.2) M⊙. The results are consistent with high luminosity SNe Ia such as SN 2003fg, SN 2006gz, SN 2007if, and SN 2009dc. There are three characteristic mass ranges of exploding WDs. In an extreme massive case, differentially rotating WDs explode as a SNe Ia soon after the WD mass exceeds 2.4 M⊙ because of a secular instability at T/|W|~0.14. For a mid mass range of MWD=1.5–2.4 M⊙, which is supported by differential rotation, it takes some spinning-down time until carbon is ignited to induce an SN Ia explosion. For a lower mass range of MWD=1.38–1.5 M⊙, they can be supported by rigid rotation until the angular momentum is lost. We also suggest the ultra super-Chandrasekhar mass SNe Ia are born in young and low metallicity environments.

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