Uchuu DR1 Halo Catalogues

The halo catalogues, provided in HDF5 format, are created using the ROCKSTAR halo finder and consisted-trees code (Behroozi et al. 2013a, Behroozi et al. 2013b). See Ishiyama et al. (2020) for details.

We provide halo catalogues for Uchuu, mini-Uchuu and micro-Uchuu. Shin-Uchuu is coming soon.
For Uchuu the number of files per snapshot is 100 with a total size ~1TB. The entire data set is 36TB.
In addition, trimmed versions (and thus smaller size) of the Uchuu halo catalogues for halos with Mvir > 1e11 Msun/h (2TB total) and Mvir > 1e12 Msun/h (132GB total) are also provided.

The table below provides the description of all 83 columns in the halo catalogues (listed in arbitrary order).

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

 desc_id

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 field from any nearby halo, in dimensionless units (Rhalo / Rhill).

Here "nearby" means within 25 Mpc/h comoving distance. This is applied only for Uchuu. mini- and micro-Uchuu do not have this limitation.

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.)