Available Datasets

Please refer to the Current Status and Policies page before proceeding.

Particle Data (Gadget)

Warning

Access to the particle data is by invite-only.

See Data Access Examples to see how to load each of these blocks. One such way is:

import haloutils as htils
hpath = htils.get_paper_paths_lx(14)[0]
zoomid = htils.load_zoomid(hpath)
blockname = "POS " # NOTE THE EXTRA SPACE!
pos = htils.load_partblock(hpath,zoomid,blockname,partids=[listofids]) # units Mpc/h

Other blocks you have access to are listed below:

Block Name Descr iptio n Units Notes
ID ID numbe r (N)
POS posit ion (Nx3) comovi ng Mpc/h They are all around ~50 Mpc/h as they are in the center of the 100 Mpc/h box for the resimul ations.
VEL veloc ity (Nx3) spatia l km\(: raw-la tex:`sqrt`( a)\)/ s Spatial velocit y. The peculia r velocit y is obtaine d by multipl ying this value by \(:raw -latex: sqrt (a)\).
``MASS` ` parti cle mass (N) Msol/h Use heade r.massa rr[1]*1 e10 as it is faster than reading in the entire block.
POT poten tial energ y  

{{site.data.alerts.warning}} Remember to use the scale factor for the snapshot you are working on to convert the comoving quantities to physical. For z = 0, it doesn’t matter.{{site.data.alerts.end}}

Halo Catalogues (Rockstar)

Attention

Access to the halo catalogues is currently public (accessible via MIT server).

Rockstar outputs a large number of halo properties.

variab le unit s defi niti on note s
id   the ID numb er of the halo  
``posX `` Mpc/ h como ving x-po siti on  
``posY `` Mpc/ h como ving y-po siti on  
``posZ `` Mpc/ h como ving z-po siti on  
pecV X km/s Pecu liar x-di r velo city  
pecV Y km/s Pecu liar y-di r velo city  
pecV Z km/s Pecu liar z-di r velo city  
core velX km/s x-di r core velo city  
core velY km/s y-di r core velo city  
core velZ km/s z-di r core velo city  
bulk velX como ving km/s x-di r bulk velo city  
bulk velY como ving km/s y-di r bulk velo city  
bulk velZ como ving km/s z-di r bulk velo city  
``mvir `` Msol /h viri al mass set by Bry an & Norm an (199 8) < http ://c dsad s.u- stra sbg. fr/a bs/1 998A pJ.. .495 …8 0B> __ pres crip tion this shou ld only be used for the mass ive host halo s - it is best to just use ``mg rav` `
mgra v Msol /h viri al mass set by Bry an & Norm an (199 8) < http ://c dsad s.u- stra sbg. fr/a bs/1 998A pJ.. .495 …8 0B> __ pres crip tion when usin g the cata logu es, only use this quan tity as it is the grav itat iona lly boun d mass of the halo - espe cial ly for subh alos
``rvir `` kpc/ h viri al radi us set by Bry an & Norm an (199 8) < http ://c dsad s.u- stra sbg. fr/a bs/1 998A pJ.. .495 …8 0B> __ pres crip tion  
chil d_r      
vmax _r km/s    
mgra v Msol /h grav itat iona l mass  
``vmax `` km/s Maxi mum circ ular velo city  
rvma x kpc/ h radi us at maxi mum circ ular velo city  
rs kpc/ h NFW scal e radi us  
``rs_k lypin` ` kpc/ h Klyp in defi ned scal e radi us bett er for smal ler halo s
``vrms `` km/s rms velo city  
Jx   x-co mpon ent angu lar mome ntum  
Jy   y-co mpon ent angu lar mome ntum  
Jz   z-co mpon ent angu lar mome ntum  
``Epot ``   Pote ntia l ener gy of the halo  
``spin ``   Peeb les defi ned spin para mete r This shou ld only be used for halo s with a larg e numb er of part icle s (~50 0+)
spin _bullo ck   Bull ock’ s modi fied spin para mete r See abov e.
``xoff ``   Posi tion offs et para mete r abs( cent er of mass posi tion - halo posi tion )  
``voff ``   Velo city offs et para mete r abs( cent er of mass velo city - halo velo city )  
b_to _a   Halo elli ptic ity b/a  
c_to _a   Halo elli ptic ity c/a  
b_to _a2   Halo elli ptic ity b/a (dif fere nt pres crip tion )  
c_to _a2   Halo elli ptic ity c/a (dif fere nt pres crip tion )  
``A[x] ``   x-ax is for elli ptic ity a  
``A[y] ``   y-xi s for elli ptic ity a  
``A[z] ``   z-xi s for elli ptic ity a  
A2[x ]   x-ax is for elli ptic ity a (dif fere nt pres crip tion )  
A2[y ]   y-xi s for elli ptic ity a (dif fere nt pres crip tion )  
A2[z ]   z-xi s for elli ptic ity a (dif fere nt pres crip tion )  
T/ab s(U)   Viri al rati o (kin etic /abs (pot enti al))  
min_ pos_er r   Mini mum erro r in posi tion  
min_ vel_er r   Mini mum erro r in bulk velo city  
``min_ bulkve l_err` `   Mini mum bulk velo city erro r.  
tota l_npar t   The tota l numb er of part icle s asso ciat ed with this halo (sub s incl uded )  
npar t   The numb er of part icle s asso ciat ed with a halo (doe s not incl ude subh alos )  

Merger Trees (consistent-trees)

Attention

Access to the halo catalogues is currently public (accessible via MIT server).

The consistent-trees output it similar to that of the rockstar catalogue except now there are additional paramters which connect the halos in time.

As listed in the previous table, consistent-trees outputs two indexes for the connecting the halos, (1) depth-first ordered or (2) breadth-first ordered. The graphic below indicates what the fundamental differences are between these two methods.