Transition Disk Chemistry and Future Prospects With Alma

Cleeves, L. Ilsedore; Bergin, Edwin A.; Bethell, Thomas J.; Calvet, Nuria; Fogel, Jeffrey K. J.; Sauter, J.; Wolf, S.

doi:10.1088/2041-8205/743/1/l2

Cited by 36 publications

(47 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The survival of molecules like CO and the chemistry of other species in dust-free cavities in transitional disks has been modeled by Bruderer 240 241 and is being tested against ALMA observations for the case of H 2 CO 242 . Molecules produced in ices may be observable as well when the disk midplane is exposed to the stellar photons at the outer edge of the cavity and molecules can be desorbed 243 . Altogether, these data form a vivid illustration and warning that gas and dust grains do not necessarily follow each other but that they need to be treated separately in the models.…”

Section: Protoplanetary Disksmentioning

confidence: 99%

Astrochemistry of dust, ice and gas: introduction and overview

Dishoeck

Ewine²

2014

Faraday Discuss.

136

102

View full text Add to dashboard Cite

A brief introduction and overview of the astrochemistry of dust, ice and gas and their interplay is presented, aimed at non-specialists. The importance of basic chemical physics studies of critical reactions is illustrated through a number of recent examples. Such studies have also triggered new insight into chemistry, illustrating how astronomy and chemistry can enhance each other. Much of the chemistry in star- and planet-forming regions is now thought to be driven by gas-grain chemistry rather than pure gas-phase chemistry, and a critical discussion of the state of such models is given. Recent developments in studies of diffuse clouds and PDRs, cold dense clouds, hot cores, protoplanetary disks and exoplanetary atmospheres are summarized, both for simple and more complex molecules, with links to papers presented in this volume. In spite of many lingering uncertainties, the future of astrochemistry is bright: new observational facilities promise major advances in our understanding of the journey of gas, ice and dust from clouds to planets.Comment: Introductory paper for Faraday Discussions 168 conference, April 201

show abstract

Section: Protoplanetary Disksmentioning

confidence: 99%

Astrochemistry of dust, ice and gas: introduction and overview

Dishoeck

Ewine²

2014

Faraday Discuss.

136

102

View full text Add to dashboard Cite

show abstract

“…The case of the observability of simulated line emission has been investigated A&A 549, A97 (2013) by Semenov et al (2008), Regály et al (2010), and Cleeves et al (2011). For the infrared wavelength range, the observability of planet-induced, large-scale disk structures was explored by Varnière et al (2006), Wolf & D'Angelo (2005), and Jang-Condell (2009).…”

Section: Introductionmentioning

confidence: 99%

Tracing large-scale structures in circumstellar disks with ALMA

Ruge

Wolf

Uribe

et al. 2013

A&A

View full text Add to dashboard Cite

Context. Planets are supposed to form in circumstellar disks. The additional gravitational potential of a planet perturbs the disk and leads to characteristic structures, i.e. spiral waves and gaps, in the disk's density profile. Aims. We perform a large-scale parameter study of the observability of these planet-induced structures in circumstellar disks in the (sub)mm wavelength range for the Atacama Large (Sub)Millimeter Array (ALMA). Methods. On the basis of hydrodynamical and magneto-hydrodynamical simulations of star-disk-planet models, we calculated the disk temperature structure and (sub)mm images of these systems. These were used to derive simulated ALMA images. Because appropriate objects are frequent in the Taurus-Auriga region, we focused on a distance of 140 pc and a declination of ≈20 • . The explored range of star-disk-planet configurations consists of six hydrodynamical simulations (including magnetic fields and different planet masses), nine disk sizes with outer radii ranging from 9 AU to 225 AU, 15 total disk masses in the range between 2.67 × 10 −7 M and 4.10 × 10 −2 M , six different central stars, and two different grain size distributions, resulting in 10 000 disk models.Results. On almost all scales and in particular down to a scale of a few AU, ALMA is able to trace disk structures induced by planet-disk interaction or by the influence of magnetic fields on the wavelength range between 0.4 and 2.0 mm. In most cases, the optimum angular resolution is limited by the sensitivity of ALMA. However, within the range of typical masses of protoplanetary disks (0.1-0.001 M ) the disk mass has a minor impact on the observability. It is possible to resolve disks down to 2.67 × 10 −6 M and trace gaps induced by a planet with Mp M = 0.001 in disks with 2.67 × 10 −4 M with a signal-to-noise ratio greater than three. The central star has a major impact on the observability of gaps, as well as the considered maximum grainsize of the dust in the disk. In general, it is more likely to trace planet-induced gaps in our magnetohydrodynamical disk models, because gaps are wider in the presence of magnetic fields. We also find that zonal flows resulting from magneto-rotational instability (MRI) create gap-like structures in the disk's re-emission radiation, which are observable with ALMA. Conclusions. Through the unprecedented resolution and sensitivity of ALMA in the (sub)mm wavelength range, the expected detailed observations of planet-disk interaction and global disk structures will deepen our understanding of the planet formation and disk evolution process.

show abstract

“…However, the resulting CO column densities are still not consistent with observations. As indicated by Cleeves et al (2011), the disk midplane in the gap region can be irradiated by the stellar radiation and X-rays. Thus, CO would not be frozen out onto grains, which would result in better gap detection rate thanks to higher contrast.…”

Section: Distribution Of the Different Molecular Speciesmentioning

confidence: 99%

“…Dutrey et al (2008) used spatially unresolved but spectroscopically resolved line observations to trace inner cavities due to the radial dependence of the (Keplerian) velocity field. Cleeves et al (2011) demonstrated the feasibility of detecting a huge inner cavity (R ∼ 45 AU) using molecular lines (CO, H 2 CO 2 ). Using ALMA, Casassus et al (2013) were able to image multiple molecular gas species within the dust free inner hole of HD 142527 and to utilize the varying optical depths of the different species to detect a flow of gas crossing the gap opened by a planet.…”

Section: Introductionmentioning

confidence: 99%

Tracing planet-induced structures in circumstellar disks using molecular lines

Ober

Wolf

Uribe

et al. 2015

A&A

View full text Add to dashboard Cite

Context. Circumstellar disks are considered to be the birthplace of planets. Specific structures like spiral arms, gaps, and cavities are characteristic indicators of planet-disk interaction. Investigating these structures can provide insights into the growth of protoplanets and the physical properties of the disk. Aims. We investigate the feasibility of using molecular lines to trace planet-induced structures in circumstellar disks. Methods. Based on 3D hydrodynamic simulations of planet-disk interactions obtained with the PLUTO code, we perform selfconsistent temperature calculations and produce N-LTE molecular line velocity-channel maps and spectra of these disks using our new N-LTE line radiative transfer code Mol3D. Subsequently, we simulate ALMA observations using the CASA simulator. We consider two nearly face-on inclinations, five disk masses, seven disk radii, and two different typical pre-main-sequence host stars (T Tauri, Herbig Ae) at a distance of 140 pc. We calculate up to 141 individual velocity-channel maps for five molecules/isotopoloques ( 12 C 16 O, 12 C 18 O, HCO + , HCN, and CS) in a total of 32 rotational transitions to investigate the frequency dependence of the structures indicated above. Results. We find that the majority of protoplanetary disks in our parameter space could be detected in the molecular lines considered. However, unlike the continuum case, gap detection is not straightforward in lines. For example, gaps are not seen in symmetric rings but are masked by the pattern caused by the global (Keplerian) velocity field. By comparison with simulated observations of undisturbed disks we identify specific regions in the velocity-channel maps that are characteristic of planet-induced structures. Conclusions. Simulations of high angular resolution molecular line observations demonstrate the potential of ALMA to provide complementary information about the planet-disk interaction as compared to continuum observations. In particular, the detection of planet-induced gaps is possible under certain conditions.

show abstract

Transition Disk Chemistry and Future Prospects With Alma

Cited by 36 publications

References 37 publications

Astrochemistry of dust, ice and gas: introduction and overview

Astrochemistry of dust, ice and gas: introduction and overview

Tracing large-scale structures in circumstellar disks with ALMA

Tracing planet-induced structures in circumstellar disks using molecular lines

Contact Info

Product

Resources

About