I am Liang, "Eric" Fu-Heng (梁赋珩),* or phonetically Liáng, Fù-Héng.
I am a postdoc in astronomy at Heidelberg University, working with Kathryn Kreckel and others. Although my institute is called Astronomisches Rechen-Institut (Astronomical Computing Institute), my work is observation-based. I work on the interaction between stars and gas to understand galaxy evolution. I use observations of nearby galaxies and our own Milky Way Galaxy from telescopes such as ALMA, VLT/MUSE, HST, SDSS, etc. I am a member of the PHANGS and SDSS-V/LVM collaborations (and previously SDSS-IV/MaNGA), where I study Wolf-Rayet stellar populations and their surrounding interstellar medium. I also analyse cold molecular gas properties and their potential of forming new stars as part of the WISDOM and ACES collaborations. More can be found in Research and Get in touch sections below.
* The Chinese convention of names puts the family name (i.e. "Liang 梁") in the front.
Stars (or the lack of new stars) drive galaxy evolution through the baryon cycle. My research studies the physical details of this picture. To put it in a simple way, a galaxy forms cold molecular gas from its accreted atomic gas, distributes (all phases of) gas via dynamical processes, and determine the properties of molecular gas clouds (see details in sub-sections No.1-2 below). Stars are born in the dense cores of giant molecular clouds when the condition is favourable (see details in sub-sections No.2-3 below). They then remove, ionise, and metal-enrich* the surrounding gas. Specifically, stars with high initial mass are the most energetic and short-lived. They leave the greatest impact on the interstellar medium. This is my current project, please stay tuned. Apart from science, I am also involved with data reduction of SDSS-V/LVM and PHANGS-MUSE. I do ALMA data reduction too. * In astronomy, metal refers to any chemical element heavier than helium.
On the left figure (click on it to enlarge), we see three beautiful disc galaxies. The cold molecular gas content traced by CO(2-1) emission is observed by ALMA and depicted with contours on the figure. The molecular gas forms a rotating disc in each galaxy but also exhibits clear asymmetric morphologies and non-circular motions. These features point to physical origins such as a past minor merger event, feedback from the active galactic nucleus, and bar-induced gas inflow towards the galactic centre. More in the paper.
As the fuel and site of upcoming star formation, the properties of cold molecular gas clouds are the key to understanding how star formation proceeds (or does not proceed). This should further answer the question of how actively star-forming galaxies transition into passive galaxies. This figure shows one of the key cloud properties, i.e. turbulence-dominated velocity dispersion (as a function of size). The data points are from a passive galaxy we studied while the black dotted line is the literature relation of the Milky Way disc. Surprisingly, cloud properties do not differ between the passive galaxy and the star-forming Milky Way disc. More in a talk here, and paper coming soon!
When stars form out of a molecular cloud, what is the initial mass distribution? This is important as stars with different initial masses have drastically different evolution paths and feedback mechanism/strength. I studied the high-mass-end power-law slope of this so-called stellar initial mass function, and found evidence of its variation with metallicity. The figure shows the Bayesian evidence ratio for the two slope assumptions (-2.70 and -2.00). The ratio (y axis) changes with metallicity (x axis). The evidence is derived from Bayesian modelling of a sample of Wolf-Rayet region spectra, which are binned by their metallicities. The three colours correspond to the three quartiles. More in the paper.
My given name (Fu-Heng 赋珩) can be interpreted as "to gift jade", and you can indeed find this specific type of jade ornament "Heng 珩" in various museums. I also naturally go by the nickname "Eric" since kindergarten.
I was born in the city of Xi'an (西安), which is the ancient capital of more than ten Chinese dynasties. The meat sandwich (Rou-Jia-Mo 肉夹馍) is great. My parents' families are originally from the provinces of Shandong (山东) and Jiangsu (江苏). I grew up in the city of Shanghai (上海), where eastern and western cultures intertwine. The small steamed bun (Xiao-Long-Bao 小笼包) is a gem. I then spent seven years in the city of Beijing (北京), which is the solemn capital now. The lamb hot pot (Shuan-Yang-Rou 涮羊肉) is amazing. After that, I lived in Oxford for three years. The full English breakfast is worth a try. I then lived one year in Munich. The beer never disappoints. And here I am now, in the beautiful little town of Heidelberg where I can see the mountains and hear the river right from my doorstep.
In my leisure time, I enjoy hanging with friends, sports, music, animation, comics, games, Go (Wei-Qi 围棋), aviation, collecting magnets from travel, reading, journaling, movies & TV-series, etc.