Uchuu DR1 Halo Catalogues

The halo catalogues are created using the ROCKSTAR halo finder and it contains also information from the Merger Trees outputs.

The halo catalogue tables are written in HDF5 format.
We provide halo catalogues for all 50 Uchuu snapshots.
The number of files per snapshot is ~4000 (total size ~1.5 TB).
Total data set is ~42 TB.


The table below provides the content of all 83 columns in our halo catalogues.

Column#

Name

Type

Unit

Description

0

 scale

float

scale factor, same as in snapshot-redshifts table

1

 id

int64

unique ID for the halo

2

 desc_scale

float

scale factor of the descendant halo, if applicable

3

 descId

int64

ID of the descendant halo, if applicable

4

 num_prog

int64

number of progenitors

5

 pid

int64

ID of least massive host halo (-1 if distinct halo)

6

 upid

int64

ID of most massive host halo (different from pid when the halo is within two or more larger halos)

7

 desc_pid

int64

pid of the descendant halo, if applicable

8

 phantom

int64

flag for phantom halos, nonzero for halos interpolated across timesteps

9

 sam_Mvir

float

Msun/h

halo mass, smoothed across accretion history; always greater than the sum of halo masses of contributing progenitors; only for use with selected semi-analytic models

10

 Mvir

float

Msun/h

halo mass (within virial radius)

11

 Rvir

float

kpc/h

halo radius (comoving)

12

 rs

float

kpc/h

scale radius (comoving)

13

 vrms

float

km/s

velocity dispersion (physical)

14

 mmp

boolean

flag indicating whether the halo is the most massive progenitor or not

15

 scale_of_last_MM

float

scale factor of the last major merger (Mass ratio > 0.3)

16

 vmax

float

km/s

maximum circular velocity (physical)

17

 x

float

Mpc/h

halo position (comoving)

18

 y

float

Mpc/h

halo position (comoving)

19

 z

float

Mpc/h

halo position (comoving)

20

 vx

float

km/s

halo velocity (physical, peculiar)

21

vy

float

km/s

halo velocity (physical, peculiar)

22

 vz

float

km/s

halo velocity (physical, peculiar)

23

 Jx

float

(Msun/h)*

(Mpc/h)*

km/s

halo angular momentum (physical)

24

 Jy

float

(Msun/h)*

(Mpc/h)*

km/s

halo angular momentum (physical

25

 Jz

float

(Msun/h)*

(Mpc/h)*

km/s

halo angular momentum (physical

26

 Spin

float

halo spin parameter

27

 Breadth_first_ID

int64

ID for breadth-first ordering of halos within a tree

28

 Depth_first_ID

int64

ID for depth-first ordering of halos within a tree

29

 Tree_root_ID

int64

ID of the halo at the last time-step in the tree

30

 Orig_halo_ID

int64

original halo ID from halo finder

31

 Snap_idx

int64

Index of snapshot (in the original snapshot list) from which halo originated

32

 Next_coprogenitor_

depthfirst_ID

int64

depthfirst ID of next coprogenitor

33

 Last_progenitor_

depthfirst_ID

int64

depthfirst ID of last progenitor

34

 Last_mainleaf_

depthfirst_ID

 

int64

depthfirst ID of last progenitor on main progenitor branch

35

 Tidal_Force

float

 

Strongest tidal force from any nearby halo, in dimensionless units (Rhalo / Rhill)

36

 Tidal_ID

int64

 

ID of halo exerting strongest tidal force

37

 Rs_Klypin

float

scale radius determined using Vmax and Mvir (see Rockstar paper)

38

 Mvir_all

float

Msun/h

Mass enclosed within the specified overdensity, including unbound particles

39

 M200b

float

Msun/h

Mass enclosed within overdensity 200*rho_b

40

 M200c

float

Msun/h

Mass enclosed within overdensity 200*rho_crit

41

 M500c

float

Msun/h

Mass enclosed within overdensity 500*rho_crit

42

 M2500c

float

Msun/h

Mass enclosed within overdensity 2500*rho_crit

43

 Xoff

float

Kpc/h

Offset of density peak from average particle position (comoving)

44

 Voff

float

km/s

Offset of density peak from average particle velocity (physical)

45

 Spin_Bullock

float

Bullock spin parameter (J/(sqrt(2)*GMVR))

46

 b_to_a

float

ratio of second largest shape ellipsoid axes to largest shape ellipsoid axis (dimensionless); shapes determined by method in Allgood et al. (2006)

47

 c_to_a

float

ratio of smallest shape ellipsoid axes to largest shape ellipsoid axis (dimensionless) ); shapes determined by method in Allgood et al. (2006)

48

 A[x]

float

Kpc/h

largest shape ellipsoid axis (comoving)

49

 A[y]

float

Kpc/h

largest shape ellipsoid axis (comoving)

50

 A[z]

float

Kpc/h

largest shape ellipsoid axis (comoving)

51

 b_to_a(500c)

float

as above but only for particles within overdensity 500*rho_crit (dimensionless)

52

 c_to_a(500c)

float

as above but only for particles within overdensity 500*rho_crit (dimensionless)

53

 A[x](500c)

float

Kpc/h

as above but only for particles within overdensity 500*rho_crit (comoving)

54

 A[y](500c)

float

Kpc/h

as above but only for particles within overdensity 500*rho_crit (comoving)

55

 A[z](500c)

float

Kpc/h

as above but only for particles within overdensity 500*rho_crit (comoving)

56

 T/|U|

float

ratio of kinetic to potential energies

57

 M_pe_Behroozi

float

Msun/h

Pseudo-evolution corrected masses (very experimental)

58

 M_pe_Diemer

float

Msun/h

Pseudo-evolution corrected masses (very experimental)

59

 Halfmass_Radius

 

float

Kpc/h

Radius within which 1/2 of Mvir is enclosed

60

 rvmax

float

Kpc/h

Radius at Vmax

61

 Macc

float

Msun/h

halo mass at accretion

62

 Mpeak

float

Msun/h

peak mass over accretion history

63

 Vacc

float

Vmax at accretion

64

 Vpeak

float

peak Vmax over accretion history

65

 Halfmass_Scale

float

scale factor at which the most massive progenitor (mmp) reaches 0.5*Mpeak

66

 Acc_Rate_Inst

float

 Msun/h/yr

instantaneous halo mass accretion rate

67

 Acc_Rate_100Myr

float

 Msun/h/yr

halo mass accretion rate averaged over past 100 Myr

68

 Acc_Rate_1*Tdyn

float

 Msun/h/yr

halo mass accretion rate averaged over past 1*virial dynamical time

 

69

 

 

 

 Acc_Rate_2*Tdyn

 

 

float

 Msun/h/yr

halo mass accretion rate averaged over past 2*virial dynamical time

70

 Acc_Rate_Mpeak

float

 Msun/h/yr

growth rate of Mpeak, averaged from current z to z+0.5

71

 Acc_Log_Vmax

_Inst

float

 Msun/h/yr

Instantaneous growth rate of Log10(Vmax)

72

 Acc_Log_Vmax

_1*Tdyn

float

 Msun/h/yr

growth rate of Log10(Vmax), averaged over past 1*virial dynamical time 

73

 Mpeak_Scale

float

scale factor at which Mpeak was reached

74

 Acc_Scale

float

scale factor at which satellites were (last) accreted

75

 First_Acc_Scale

float

scale factor at which current and former satellites first passed through a larger halo

76

 First_Acc_Mvir

float

Msun/h

Mvir at First_Acc_scale

77

 First_Acc_Vmax

float

km/s

Vmax at First_Acc_scale

78

 Vmax@Mpeak

float

km/s

halo Vmax at the scale at which Mpeak was reached

79

 Tidal_Force_Tdyn

float

Dimensionless tidal force averaged over past dynamical time

80

 Log_(Vmax/Vmax

_max(Tdyn;Tmpeak))

float

Log10 of Vmax_now over Vmax@(Tdyn ago) OR Vmax@Mpeak (if and only if Mpeak happened > 1Tdyn ago)

81

 Time_to_future

_merger

float

Gyr

Time (in Gyr) until the given halo merges into a larger halo.  (-1 if no future merger happens)

82

 Future_merger_

MMP_ID

int64

most-massive progenitor of the halo into which the given halo merges. (-1 if the main progenitor of the future merger halo does not exist at the given scale factor.)