MaNGA Tech Group 2018-06-26

MaNGA Technical Group

Possible Porjects

A list:

1. Emission-line measurements, and the morphology distribution of different emission lines (science drive not yet clear)
2. The stellar population analysis of type I AGNs
3. The lick indices of type I AGNs
4. Balmer decrements of broad and narrow emission lines of type I AGNs
5. Outflow
6. LSB in type I AGNs
7. Velocity dispersion distributions of type I AGNs

B list:

1. AGN metallicity measurements
2. [FeII] lines
3. TBD

Some explanations

(A) list are projects we discussed in the morning that seems to be promising: either that the science motivations are clear, or that they are directions that worth exploring. (A) list projects so far have all been assigned or claimed by somebody. (B) list are projects that may be interesting, but we are not yet sure exactly how to carry them out..

A1) is not linked to any specific science, instead, it is the basis for many following projects.

A2) and A3) is about getting the stellar populations of type I AGNs. Later on, this method can be expanded to include type II AGNs, and compare their stellar populations with those of type I AGNs. This is a scientifically clearly-defined project.

A4) measure and compare the Balmer decrements of broad and narrow emission lines of AGNs. The science drive is clear. However, may need to check similar work done with the SDSS spectra. The advantages of using 2D data, is that now we can study the extinction profiles (as a function of radius) of various emission line regions, particularly if there are extended narrow-line regions exist. Broad-line regions are so far all point sources, but we can still check if the Balmer decrements measured at different spexels are different, this will help evaluate how people can be wrong with a single-fiber SDSS spectrum.

A5) Outflow science is interesting, but as I mentioned, clear conclusion can be difficult to get, as there are many things to check (using \sigma or v, where to cut the criteria, how to understand and make use of the morphology information, etc), so for now, may just check whether [OIII] lines in the sample are broad, and the morphology of this extra component.

A6) use the list (not the MaNGA datacube), to find out their disk properties (use the Meert catalog), and evaluate if there are low-surface-brightness galaxies in the sample.

A7) Using the MaNGA DAP data, plot the distribution of the stellar velocity distribution of the sample. While plotting, also note where the bulges and disks are in each distribution.

B1)Lei Hao needs to find out references of whether we can use all these emission lines to figure out the metallicity. And future projects may depend on the finding results.

Who might be doing what?

• Li Zhenzhen needs to do more preparation for the sample: generate a list containing the path that points directly to the datacube for each galaxy. Match to find out the SDSS DR7 plate, fiber, mjd information for each galaxy.
• A1) Li Zhenzhen and Ju Mengting will do this with two different methods. Li Zhenzhen will measure each line independently with multi-Gaussians, while Ju Mengting will measure all narrow-lines together with one uniform line width (and try two methods to get rid of the effects of broad emission lines).
• A2) Feng Shuai
• A3) Feng Shuai and Yin Jun
• A4) Liu Rongrong and Lu Jiafeng
• A5) Li Huan, will do some Gaussian fitting for [OIII] line only
• A6) Huang Xiangning
• A7) Zhou Yipeng
• B1) Lei Hao find references.