text stringlengths 128 2.05k |
|---|
[MATH] [MATH] 0.33. Our PSF-subtracted [MATH] -band image shows possible emission interior to the 86.3 AU ring; however, this structure may have been |
4. A Two Grain Model 4.1. Thermal-Emission Single-temperature black bodies grains and power-law size distributions of olivine grains are inadequate for reproducing the observed HD 181327 grain properties. (1) Black body grains in radiative equilibrium, located at a distance of 86 AU around a [MATH] = 3.1 [MATH] [MATH] ... |
While the MIPS SED-mode data have very low resolution (R [MATH] 15-25) and do not cover the 40 - 55 [MATH] m range, the 60-75 [MATH] m peak indicates emission from a relatively broad solid state feature. Since water ice is expected to be abundant and crystalline water ice possesses a well-studied emission plateau at 40... |
We model the observed SED by summing over the thermal-emission produced by each species, requiring that both the amorphous olivine and water-ice grains are located at 86.3 AU, consistent with the 1.1 [MATH] m scattered-light image |
[EQUATION] where [MATH] is the grain radius, [MATH] is the grain size distribution with minimum grain radius, [MATH] , and maximum grain radius, [MATH] [MATH] and [MATH] are the absorption efficiency and temperature of grain species, [MATH] , and [MATH] is the distance from the observer to the star. We estimate the min... |
[MATH] 0.5 will be gravitationally bound: [EQUATION] (Burns et al. 1979; Artymowicz 1988), where [MATH] (= 3.1 [MATH] ) and [MATH] (= 1.4 [MATH] ) are the luminosity and mass of HD 181327, [MATH] [MATH] |
[MATH] is the radiation pressure efficiency averaged over the stellar spectrum, and [MATH] is the species density. For HD 181327, we estimate minimum grains sizes, [MATH] = 1.0 and 1.5 [MATH] m for amorphous olivine ( [MATH] = 3.71 g cm -3 ) and water ice ( [MATH] = 0.92 g cm -3 ), respectively. We set [MATH] = 20 [MAT... |
[MATH] 100 [MATH] m, the presence of larger grains should not dramatically impact our SED model. We let [MATH] be a free parameter and require that [MATH] be the same for both the olivine and ice distributions. |
We reproduce the observed SED using 6.4 [MATH] 10 25 g amorphous olivine grains with [MATH] [MATH] [MATH] (with estimated [MATH] = 48 - 93 K) and 2.0 [MATH] 10 25 g of water ice grains also with [MATH] |
[MATH] [MATH] (with estimated [MATH] = 39 - 50 K; see Fig. ). Our model SED possesses a reduced [MATH] value of 22; it is slightly deficient in flux at wavelengths 30 [MATH] [MATH] |
[MATH] [MATH] 55 [MATH] m. Our T-ReCS image raises the possibility that there may be additional dust grains interior to the ring that we have not included in our model. If such warm dust grains exist, then their emission may account for the discrepancy between our observed and synthetic SEDs. Numerical simulations of c... |
4.2. Scattered-Light We estimate the scattered-light surface brightness, ν,sca,s , radius, [MATH] , and size column density distribution, [MATH] |
[EQUATION] (Augereau & Beust 2006), where L ∗,ν is the specific luminosity of the star, [MATH] is the distance to the grains, and [MATH] is the scattering phase function of species, [MATH] . The specific luminosity of the star can be inferred from its observed flux and distance, [MATH] , where [MATH] pc is the stellar ... |
[EQUATION] (Henyey & Greenstein 1941), where the scattering angle, [MATH] , is the angle of deviation from forward scattering. If the dust is azimuthally symmetric, then we estimate a 1.1 [MATH] m scattered-light surface brightness, SB = 0.81 mJy arcsec -2 at [MATH] = 86.3 AU and [MATH] = 90 [MATH] (the disk ansa), con... |
In addition to the scattered-light surface brightness, the ACS and NICMOS observations make two additional measurements of the grain population around HD 181327. Schneider et al. (2006) report a scattered-light disk color [F606W]-[F110W] = 0.5 [MATH] 0.3 mag at [MATH] . The dust grains in our model possess a color [F60... |
[MATH] [MATH] 0.33 in our discussion of the resolved thermal-emission (§3). The dust grains in our model possess [MATH] = 0.87, substantially higher than inferred from the scattered light observations, because water ice forward-scatters light efficiently independent of grain size. The large discrepancy between the obse... |
5. Discussion Recent theoretical work suggests that [MATH] m-sized water ice grains around A- and F-type main sequence stars are more effectively destroyed via photo-desorption by stellar ultra-violet photons than by sublimation (Grigorieva et al. 2007). We estimate the water ice grain erosion rate due to photo-desorpt... |
[EQUATION] where [MATH] is the fraction of the surface covered by ice, [MATH] is the mass of a water molecule (= 3 [MATH] 10 -23 g), [MATH] is the density of water ice (=0.92 g cm -3 ), [MATH] is the desorption efficiency at ultraviolet wavelengths (=10 -3 ), and [MATH] is the flux of absorbed photons at the location o... |
[EQUATION] where [MATH] is the specific stellar luminosity, [MATH] (= 0.091 [MATH] m), and [MATH] (= 0.24 [MATH] m) (Grigorieva et al. 2007). We estimate that the flux of absorbed ultra-violet photons that desorb water molecules from ice grains, [MATH] = 4.3 [MATH] 10 11 photon s -1 cm -2 , at [MATH] = 86.3 AU, assumin... |
[MATH] m yr -1 if the surface of the grains are 99.9% water ice and 0.1% amorphous carbon ( [MATH] = 0.999), corresponding to a photo-desorption lifetime of 1400 yr for grains with radii, [MATH] = 1.5 [MATH] m, similar to the estimated collision timescale for grains in this system ( [MATH] 1300 yr; Chen et al. 2006). S... |
The cold grain temperatures ( [MATH] [MATH] 100 K; Meyer et al. 2007) in debris disks has led to speculation that these systems are icy Kuiper Belt analogs; however, the difficulty in detecting mid-infrared spectral features from these systems (Chen et al. 2006; Jura et al. 2004) makes confirmation of this supposition ... |
6. Conclusions We have obtained a T-ReCS -band (18.3 [MATH] m) image and a 55 - 90 [MATH] m MIPS SED-mode spectrum of HD 181327, an F5/F6V star in the [MATH] Pic moving group with a resolved scattered-light disk. Based on our analysis of the multi-wavelength imaging and spectroscopy, we conclude the following: |
1. The northern arm of the HD 181327 disk is 1.4 times brighter than the southern arm in thermal-emission, suggesting that either the density and/or the temperature of the grains in this region is higher than in the southern arm of the disk. |
2. The overall properties of the unresolved spectral energy distribution (at 5.5 - 90 [MATH] m), the resolved thermal-emission at 18.3 [MATH] m, and the resolved scattered-light at 1.1 [MATH] m can be reproduced by a population of 1 - 20 [MATH] m amorphous olivine and crystalline water ice grains located at a distance ... |
3. Since the estimated photo-desorption lifetime of 1.5 [MATH] m water ice grains is 1400 yr, significantly shorter than the age of HD 181327, the grains must be replenished from a reservoir such as collisions among parent bodies, perhaps Kuiper Belt objects. |
We would like to thank J. Kessler-Silacci and A. Noriega-Crespo for their assistance with the preliminary SED-mode data reduction and S. Sandford for providing an electronic copy of the laboratory measured optical constants of ices published in Hudgins et al. (1993). We would also like to thank J. Debes, M. Jura, C. Mc... |
# Source: arxiv 0808.2294 # Title: Sound Waves Excitation by Jet-Inflated Bubbles in Clusters of Galaxies # Sections: all # Downloaded: 2026-03-02T07:58:46.251799+00:00 |
SOUND WAVES EXCITATION BY JET-INFLATED BUBBLES IN CLUSTERS OF GALAXIES Abstract We show that repeated sound waves in the intracluster medium (ICM) can be excited by a single inflation episode of an opposite bubble pair. To reproduce this behavior in numerical simulations the bubbles should be inflated by jets, rather t... |
Subject headings: (galaxies:) cooling flows galaxies: clusters: general galaxies: jets INTRODUCTION Higher X-ray emissivity arcs, termed ripples, are observed in the intracluster medium (ICM) of the Perseus cluster (Fabian et al. 2003, 2006; Sanders & Fabian 2007), as well as in A2052 (Blanton et al. 2007). The ripples... |
To obtain repeated sound waves previous numerical simulations assumed repeating bubble inflation episodes (e.g., Ruszkowski et al. 2004a,b; Sijacki & Springel 2006a, b). This had to be done because these simulations used artificial bubbles , i.e., numerically injected spherical bubbles at off-center locations, as is co... |
In previous works we found that in order for the jets to inflate fat bubbles they should have a large opening angle, or they should rapidly precess (Soker 2004, 2006; Sternberg et al. 2007; Sternberg & Soker 2008a). In addition, jets that are relatively slow, |
[MATH] , and with a mass loss rate of the order of [MATH] (for both jets), are more likely to inflate fat bubbles. The same results can be seen in the simulations of Omma et al. (2004), Alouani Bibi et al. (2007) and Binney et al. (2007), who use similar parameters to ours, but instead of conical jets with wide opening... |
[MATH] in one jet. In this paper we continue our study of jet-inflated bubbles, and show that such bubbles can excite several consecutive sound waves without the need to invoke periodic jet launching episodes. We do not deal with the propagation of sound waves and their properties. These seem to require more sophistica... |
NUMERICAL METHOD AND SETUP The simulations were performed using the Virginia Hydrodynamics-I code (VH-1; Blondin et al. 1990; Stevens et al. 1992), as described in Sternberg & Soker (2008b). In this paper we mention only the important features of the code. The unperturbed ICM temperature is set to |
[MATH] . Gravity is included, but radiative cooling is not included. We study a three-dimensional axisymmetric flow with a 2D grid (referred to as 2.5D). We simulate half of the meridional plane using the two-dimensional version of the code in spherical coordinates. The symmetry axis of all plots shown in this paper is... |
We run two cases. In the wide jets case, the two opposite jets were injected at a radius of [MATH] , with constant mass flux of [MATH] per one jet, and a constant radial velocity of |
[MATH] , inside a half opening angle of [MATH] The total power of the two jets is [MATH] The jets were active for a period of [MATH] from [MATH] until [MATH] . For more detail on the numerical code and the properties of the bubbles see Sternberg & Soker (2008b). |
In the case of the precessing jets the two opposite jets were injected at a radius of [MATH] with [MATH] per one jet, and a constant radial velocity of [MATH] |
(the same parameters of the wide jets), but within a half opening angle of [MATH] . In our axisymmetric code the jets are precessing very rapidly around the symmetry axis (i.e., in 3D we actually inject a torus). We vary the angle between the symmetry axis and the jets’ axis [MATH] in a random way. Namely, the jet axis... |
[MATH] . This is done by changing [MATH] periodically and taking [MATH] to be constant. The precession period, i.e., the time the jet returns to the same angle [MATH] , is |
[MATH] . The jet’s interaction with the ICM is similar to that of a wide jet with a half opening angle of [MATH] . The jets were active for a duration of [MATH] between [MATH] and |
[MATH] . Gravity was included as was in the wide jets case. RESULTS 3.1 Wide jets In Fig. we show the density and velocity map of the wide-jet-inflated bubble at [MATH] Myr, and at [MATH] when the jet is shut off. There are some flow structures which characterize the jet-inflated bubble that are not present when artifi... |
In Fig. we omit low densities (i.e., the bubble material) and show only the high density regions of the ICM. Therefore, the bubble interior is white. The density scale is logarithmic scale of cgs units (i.e., |
[MATH] ), emphasizes the small density variations resulting from the sound waves and weak shocks excited by the bubble. Several dense arcs are seen in the ICM as they expand outward. We note the dense arc at the right-bubble front at times [MATH] [MATH] , and [MATH] Myr, but at [MATH] Myr the density close to the bubbl... |
The main morphological feature we obtain is the presence of several ripples along each radial direction. The outermost ripple is a weak shock, while the ripples closer to the bubbles are the crests of sound waves. The sound waves are excited by the corrugated boundary of the bubble that is formed mainly by the vortices... |
To better explore the properties of the waves we show the density, pressure, and temperature along three radial cuts at angles of [MATH] [MATH] |
and [MATH] , in respect to the positive direction of the [MATH] -axis, at two times, [MATH] Myr and [MATH] Myr (corresponding to the lines indicated in the two late panels in ). The typical pressure variations from the average, along these radial cuts, are [MATH] . Although the small perturbations are somewhat lower th... |
[MATH] (Rafferty et al. 2006). The density in the central region of [MATH] is similar to that in Perseus (Fabian et al. 2003). As we did not try to fit the bubbles of Perseus, we do not expect a perfect match. Varying the jets properties can lead to a better fit. In this paper we limit ourself to presenting the basic p... |
3.2 Precessing jets In Fig. we omit low densities (i.e., the bubble material), and show only the high density regions of the ICM. Therefore, the bubble interior is white. The density scale is logarithmic scale of cgs units (i.e., [MATH] ). As with the wide jets, several ripples are seen in the ICM as they expand outwar... |
In figure we show the density, pressure, and temperature along three radial cuts at angles of [MATH] [MATH] and [MATH] in respect to the positive direction of the [MATH] -axis, at two times, [MATH] Myr and [MATH] Myr (corresponding to the lines indicated in the two late panels in ). The typical pressure variations from... |
DISCUSSION AND SUMMARY We followed the response of the ICM to the inflation of bubbles by jets. The inflation of a bubble by a jet results in vortices inside the bubble and a backflow of the ICM around the bubble (Sternberg et al. 2007; Sternberg & Soker 2008a, b). Both processes cause the bubble-ICM to change shape wi... |
3.2 ), the changes in the jet axis cause a more prominent change in the bubble-ICM shape. This motion of the bubble-ICM boundary sends shocks and sound waves into the ICM. This effect cannot be reproduced by artificial bubbles, i.e., by numerically inserting spherical bubbles at off-center locations. |
Our main result is that one episode of a bubble pair inflation can excite several sound waves along each radial direction. These form high-density arcs, the ripples. The front ripple is actually a weak shock. There is no need to introduce periodic (or semi-periodic) episodes of bubble inflation. Nonetheless, multiple e... |
We also observe a dense arc at the bubble’s front that is apparent part of the time. The dense arc is the excitation of a new sound wave at the compression phase. Part of the time the region at the bubble’s front is at the rarefaction phase, the wave trough, and no dense arc is observed there. |
Our results can be incorporated into a broader scope. In a previous paper (Sternberg & Soker 2008b) we found that to follow the evolution of bubbles in the ICM one must inflate them by jets, rather than introduce them artificially. The evolution of bubbles and their influence on the ICM, e.g., sound waves, is crucial f... |
We thank John Blondin for his immense help with the numerical code. This research was supported by the Asher Fund for Space Research at the Technion, and by the Israeli Science Foundation (grant No. 89/08). |
# Source: arxiv 0808.2313 # Title: The impact of dust on the scaling properties of galaxy clusters # Sections: all # Downloaded: 2026-03-02T07:58:47.483235+00:00 |
The impact of dust on the scaling properties of galaxy clusters Abstract We investigate the effect of dust on the scaling properties of galaxy clusters based on hydrodynamic [MATH] -body simulations of structure formation. We have simulated five dust models plus a radiative cooling and adiabatic models using the same i... |
keywords: cosmology, galaxies: clusters, methods: numerical Introduction From the first stages of star and galaxy formation, non-gravitational processes drive together with gravitation the formation and the evolution of structures. The complex physics they involve rule the baryonic component within clusters of galaxies... |
Loewenstein ( 2006 ). These ejecta are then mixed in the environment by the action of the surrounding gravitational potential and the dynamics of cluster galaxies within. |
Since long, X-ray observations have shown the abundant presence of heavy elements within the ICM (see for instance review works by |
(Sarazin, 1988 ; Arnaud, 2005 ). Physical processes like ram-pressure stripping, AGN interaction with the ICM, galaxy-galaxy interaction or mergers are scrutinized within analytical models and numerical simulations in order to explain the presence of metals (see for instance works by (Kapferer et al., 2006 ; Domainko e... |
(Murante et al., 2004 2007 ; Conroy & Ostriker, 2007 have stressed the role of hierarchical buiding of structures in enriching the ICM with stars in a consistent way with the observed amount of ICM globular clusters, and ICM light. Indeed, the overall light coming from stars in between cluster galaxies represent an imp... |
(Montier & Giard, 2004 . These authors have computed the cooling function of dust taking into account the energetic budget for dust. They have shown the ability of dust to be a non negligible cooling/heating vector depending on the physical properties of the environment. |
Dust thus comes, within the ICM/IGM, as an added source of non-gravitational physics that can potentially influence the formation and the evolution of large scale structure in a significant way. Indeed, since redshift of [MATH] during which the star formation activity reached its maximum in the cosmic history, large am... |
In order to tackle this question, we have put into place the first N-body numerical simulations of hierarchical structure formation implementing the cooling effect of dust according to the dust nature and abundance. In this paper, we present the first results of this work focusing at the scale of galaxy clusters, and m... |
The dust model In our numerical simulations the implementation of the physical effect of dust grains is based on the computation by Montier & Giard ( 2004 of the dust heating/cooling function. In this work, we decided to limit our implementation to the dust cooling effect only. Indeed the goal of this paper is to study... |
Dust grains in a thermal plasma with [MATH] K are destroyed by thermal sputtering, which efficiency was quantified by Draine & Salpeter ( 1979 , see their Eq. 44) . The sputtering time depends on the column density and on the grain size. For grain sizes ranging form [MATH] m to [MATH] m, and an optically thin plasma ( ... |
Our implementation of the dust cooling power is based on the model by (Montier & Giard, 2004 . We recall bellow the main aspects of this model and describe the practical implementation within the [MATH] -body simulations. |
2.1 The dust cooling function Dust grains within a thermal gas such as the ICM or the IGM can either be a heating or a cooling vector depending on the physical state of the surrounding gas and on the radiative environment. Heating can occur via the photo-electric effect if the stellar radiation field (stars and/or QSOs... |
Montier & Giard ( 2004 have computed the balance of the heating and cooling by dust with respect to the dust abundance: cooling by dust dominates at high temperatures in the hot IGM of virialized structures (i.e clusters of galaxies), and heating by dust dominates in low temperature plasma under high radiation fluxes s... |
Assuming local thermal equilibrium for the dust, the overall balance between heating and cooling in dust grains can be written as follows: |
[EQUATION] with [MATH] being the collisional heating function of the grain and [MATH] the cooling function due to thermal radiation of dust. [MATH] is the grain size, [MATH] and [MATH] are respectively the electronic temperature and density of the medium and [MATH] is the dust grain temperature. |
The heating of the dust grain was taken from Dwek ( 1981 and can be expressed in a general way as: [EQUATION] where the values of [MATH] and [MATH] are dependent of the value of the ratio [MATH] |
The relevant dust parameters affecting the cooling function are the grain size and the metallicity. Indeed, the smaller the grains and the higher the metallicity, the higher is the cooling power of the dust. Thus the total cooling function due to a population of dust grains can be expressed as a function of these two p... |
[EQUATION] where [MATH] is the differential number of dust grains per size, metallicity and volume element. Cooling by dust happens to increase with the square root of the gas density, whereas the heating by dust is proportional to the density. As stressed by Montier & Giard ( 2004 the cooling by dust is more efficient... |
[MATH] keV), which is typically the IGM and ICM thermal conditions. We redirect the reader to Montier & Giard ( 2004 for a full description of the dust model, and a comprehensive physical analysis of the effect of dust in a optically thin plasma. |
2.2 The dust abundance The abundance of dust is a key ingredient to properly weight in our implementation. Observations indicate that dust represents only a tiny fraction of the baryonic matter: [MATH] |
in our Milky Way (Dwek et al., 1990 , and this is possibly lower by a factor 100 to 1000 in the ICM: [MATH] (Popescu et al., 2000 ; Aguirre et al., 2001 . We defined the abundance of dust as the ratio of the dust mass with respect to the gas mass: |
[EQUATION] where [MATH] is the metallicity in units of solar metallicity, [MATH] is the solar dust abundance, i.e the dust-to-gas mass ratio in the solar vincinity (Dwek et al., 1990 , and [MATH] is the abundance of dust in the ICM in units of solar dust abundance. |
Dust enrichment occurs via the feedback of galaxy formation and evolution in the ICM through interaction, stripping, mergers, galactic winds and AGNs outburst. At all redshifts, it is linked to the SFR which drives the production of dust in cluster galaxies. However, in our hydrodynamic simulations (see Sect. ) the SFR... |
2.3 Implementation in the [MATH] -body simulations From the equations presented in the previous sections, we computed the dust cooling function according to the embedding medium temperature and (global) metallicity. In simulations, once the metallicity and temperature are known, [MATH] and [MATH] are the only two param... |
[MATH] and [MATH] [MATH] m (model D1, see below) at different values of metallicity. The blue and black lines are the radiative cooling rates from Sutherland & Dopita ( 1993 and the total (i.e radiative plus dust cooling) rate, respectively. |
Together with an adiabatic run (i.e model A) and a “standard” radiative run (model C – see Sect. for further details), we ran a total of five runs implementing various population of grains (i.e named D1 to D5) characterized by their sized and dust-to-metal mass ratio: |
We tested three types of sizes: two fixed grain sizes with [MATH] [MATH] m and [MATH] [MATH] m), respectively labeled small and big . The third assumes for the IGM dust grains a distribution in sizes as defined by Mathis et al. ( 1977 for the galactic dust: [MATH] within the size interval of [MATH] |
[MATH] m. It is hereafter referred as the ‘MRN’ distribution. We investigate three values of [MATH] [MATH] [MATH] and [MATH] . The two extreme values roughly bracket the current theoretical and observational constraints on dust abundance in the ICM/IGM (i.e [MATH] and [MATH] in terms of dust-to-gas mass ratio) (Popescu... |
Tab. lists code names and simulation details of all runs used in this work. In case of models D1 to D5, simulation cooling rates are given by the added effect of cooling due to dust and radiative gas cooling. Total cooling functions are displayed (non-coloured lines) in the bottom panel of Fig for each of these models ... |
[MATH] . As the Figure indicates, the effect of dust cooling is stronger for models with higher dust-to-metal mass abundance parameters, [MATH] , and for smaller grain sizes (model D1). For low values of [MATH] the impact of dust cooling is significantly reduced. For example, in the case of model D5, the contribution o... |
Numerical Simulations 3.1 Simulation description Simulations were carried out with the public code package Hydra (Couchman et al., 1995 ; Pearce & Couchman, 1997 , an adaptive particle-particle/particle-mesh (AP M), (Couchman, 1991 |
gravity solver with a formulation of smoothed particle hydrodynamics (SPH), see Thacker & Couchman ( 2000 , that conserves both entropy and energy. In simulations with cooling gas particles are allowed to cool using the method described in Thomas & Couchman ( 1992 and the cooling rates presented in previous Section. At... |
[MATH] is the solar metallicity and [MATH] is the age of the universe in units of the current time. All simulations were snapshot, at [MATH] . The initial density field was constructed, using |
[MATH] particles of baryonic and dark matter, perturbed from a regular grid of fixed comoving size [MATH] . We assumed a [MATH] -CDM cosmology with parameters, [MATH] |
[MATH] [MATH] [MATH] [MATH] . The amplitude of the matter power spectrum was normalized using [MATH] . The matter power spectrum transfer function was computed using the BBKS formula (Bardeen et al., 1986 , with a shape parameter [MATH] given by the formula in |
Sugiyama ( 1995 . With this choice of parameters, the dark matter and baryon particle masses are [MATH] and [MATH] respectively. The gravitational softening in physical coordinates was |
[MATH] below [MATH] and above this redshift scaled as [MATH] We generate a total of 7 simulation runs, listed in Table . The first two runs, which will be referred hereafter as ‘adiabatic’ (or model ’A’) and ‘cooling’ (or model ’C’) simulations, do not include dust. Simulations 3 to 7 differ only on the dust model para... |
3.2 Catalogue construction Cluster catalogues are using a modified version of the Sussex extraction software developed by Thomas and collaborators (Thomas et al., 1998 ; Pearce et al., 2000 ; Muanwong et al., 2001 . Briefly, the cluster identification process starts with the creation of a minimal-spanning tree of dark ... |
(Eke, Navarro & Frenk, 1998 . A sphere is then grown around the densest dark matter particle in each clump until the enclosed mass verifies |
[EQUATION] where [MATH] is a fixed overdensity contrast, [MATH] is the critical density and [MATH] . Cluster properties are then computed in a sphere of radius [MATH] , ie with |
[MATH] , for all objects found with more than 500 particles of gas and dark matter. This means that our original catalogues are complete in mass down to [MATH] . For the study presented in this paper we have trimmed our original catalogues to exclude galaxy groups with masses below [MATH] . In this way the less massive... |
Cluster properties investigated in this paper are the mass, [MATH] mass-weighted temperature, [MATH] and entropy, [MATH] (defined as [MATH] ), integrated Compton parameter, [MATH] (i.e roughly the SZ signal times the square of the angular diameter distance to the cluster), and core excised (50 [MATH] kpc) X-ray bolomet... |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.