nemo3::tof_tools Class Reference

Utils for Time of Flight calculation. More...

#include <tof_tools.h>

List of all members.

Public Member Functions
	tof_tools ()
	default constructor
	tof_tools (bool debug_, bool use_energy_loss_=false, bool timeerr_=false, bool fluct_=false)
	constructor with options on debug, energy loss, time error, laser fluctuation
	~tof_tools ()
	Default destructor.
void	init_from (const datatools::utils::properties &)
	Can be init from config file. Not used yet.
void	set_debug (bool debug_)
	debug additional output
void	set_run_number (int run_number_, std::string runtype_="")
	run number for database, usually indispensable
void	set_ECorr (bool energy_loss_)
	If taking care of energy correction.
void	set_TimeErr (bool timeerr_)
	If taking care of time error from laser.
void	set_LTFluct (bool fluct_)
	If taking care of laser fluctuation.
void	set_simulation (bool simu_)
	If the run is from simulation.
void	set_nodb4simu (bool nodb_)
	To not access to the DB for simulation.
void	set_tau_sc (double ts_)
	Custom electron scintillator transit time.
void	set_tau_sc_g (double ts_)
	Custom gamma scintillator transit time.
void	set_tau_el (double ts_)
	Custom electronics delay.
void	set_Vg (double vg_)
	Custom number of photo electron correction.
void	set_run_type (std::string rt_)
	Run type (betabeta or noalpha)
bool	get_simulation ()
	is simulation set true
string	get_run_type ()
	what is the run type set
bool	get_dt (const track &track1_, const track &track2_, double &dt_int_, double &dt_ext_)
	get time difference between theoretics and measured ToF of two electrons.
bool	get_dt (const track &track1_, const scin_hit &scin_hit2_, double &dt_int_, double &dt_ext_, bool change_elec_energy_=false, double elec_energy_=0, double elec_length_=0)
	get time difference between theoretics and measured ToF of an electron and a gamma.
bool	get_dt (const scin_hit &scin_hit1_, const scin_hit &scin_hit2_, double &dt_)
	get time difference between theoretics and measured ToF of two gamma.
bool	get_chi2 (const track &track1_, const track &track2_, double &internal_chi2_, double &external_chi2_, bool keep_dt_=false)
	Calculate the chi2 between two electrons for a given dt.
bool	get_chi2 (const track &track_, const scin_hit &scin_hit_, double &internal_chi2_, double &external_chi2_, bool keep_dt_=false, bool change_elec_energy_=false, double elec_energy_=0, double elec_length_=0)
	Calculate the chi2 between an electron and a gamma for a given dt.
bool	get_chi2 (const scin_hit &scin_hit1_, const scin_hit &scin_hit2_, double &chi2_, bool keep_dt_=false)
	Calculate the chi2 between two gammas scin to scin for a given dt.
bool	get_chi2_1e (const scin_hit &scin_hit1_, const scin_hit &scin_hit2_, double &internal_chi2_, double &internal_prob_)
	Calculate the chi2 for one electron scin to scin for a given times.
bool	get_chi2_2e_1g (const track &track1_, const track &track2_, const scin_hit &scin_hit3_, const bool switch_, double &internal_chi2_, double &internal_prob_)
	Calculate the chi2 between two electrons and a gamma for given times.
bool	get_chi2_2e_2g (const track &track1_, const track &track2_, const scin_hit &scin_hit3_, const scin_hit &scin_hit4_, const bool switch_, double &internal_chi2_, double &internal_prob_)
	Calculate the chi2 between two electrons and two gammas for given times.
bool	get_chi2_2g (const track &track_, const scin_hit &scin_hit2_, const scin_hit &scin_hit3_, const bool switch_, double &internal_chi2_, double &internal_prob_, bool change_elec_energy_=false, double elec_energy_=0, double elec_length_=0)
	Calculate the chi2 between one electron and two gammas for given times.
bool	get_chi2_3g (const track &track_, const scin_hit &scin_hit2_, const scin_hit &scin_hit3_, const scin_hit &scin_hit4_, const bool switch_, double &internal_chi2_, double &internal_prob_, bool change_elec_energy_=false, double elec_energy_=0, double elec_length_=0)
	Calculate the chi2 between one electron and tree gammas for given times.
void	set_vera (bool vera_)
	useless
Static Public Member Functions
static void	get_proba (double internal_chi2_, double external_chi2_, double &internal_prob_, double &external_prob_, unsigned int freedom_=1)
	Get probability for freedom_ degree of freedom.
Private Member Functions
float	get_tse (int sector_, int iobt_, int fcll_, int block_)
	internal method to get the time sigma error from N3Db
float	get_ltce (int sector_, int iobt_, int fcll_, int block_)
	internal method to get the laser time calibration error from N3Db
float	get_ltfluct (int sector_, int iobt_, int fcll_, int block_)
	internal method to get the laser time fluctuation
double	Beta (double ke_, double mass_)
	internal method to get the relativistic beta factor for an energy ke_ and a mass mass_
double	T_th (double ke_, double mass_, double trlen_)
	internal method to get the theoretics time of flight
double	ECorrTracking (double energy_, double trlen_, scin_hit_id &id_)
	correct the energy of a particle
double	SigmaE (scin_hit_id &id_, double ke_)
	sigma from laser measurement
double	SigmaTrlen (double mass_)
	error on PM size. A bit more than size/2
double	SigmaT (scin_hit_id &id_, double ke_, bool gamma_=false)
	Total transition time error.
double	FWHM (scin_hit_id &id_)
	Get the FWHM of the scin from N3Db.
double	g_trlen (geomtools::vector_3d &vertex_, scin_hit_id &id_)
	get track length for a gamma, from vertex to scintillator
double	g_trlen (scin_hit_id &id1_, scin_hit_id &id2_)
	get track length for a gamma from a scintillator to another scintillator
Private Attributes
bool	__debug
	additional verbose information
bool	__use_energy_loss
	if use energy losses for electrons
bool	__use_ltfluct
	if use laser time fluctuation
bool	__use_time_err
	if use time error from laser
bool	__simulation
	if the run is simulation
bool	__vera_method
	useless
bool	__nodb4simu
	do not you the DB for simulation
int	__run_number
	the current run number
double	__t1
	the kept time during get_dt
double	__t2
	the kept time during get_dt
double	__t_th1_int
	the kept time during get_dt
double	__t_th2_int
	the kept time during get_dt
double	__t_th1_ext
	the kept time during get_dt
double	__t_th2_ext
	the kept time during get_dt
double	__dt_int
	the kept dt during get_dt
double	__dt_ext
	the kept dt during get_dt
double	__dt
	the kept dt during get_dt
double	__e1
	the kept corrected energy during get_dt
double	__e2
	the kept corrected energy during get_dt
double	__e_last
	the kept corrected energy during get_dt
string	__run_type
	the type of the run (betabeta or noalpha)
Static Private Attributes
static const double	kC
	speed of light in cm.ns-1
static const double	kMe
	electron mass in keV
static const double	kSig
	\( 2*\sqrt{2*ln 2} \)
static double	kTauSc
	decay scintillator time constant
static double	kTauSc_g
	decay scintillator time constant
static double	kTauEl
	electronic and other independant cst
static double	kVg
	number of photoelectron correc
static double	fwhm_trans
	FLUCTUATIONS IN TRANSIT TIME IN THE PMT (ns)

---

Detailed Description

Utils for Time of Flight calculation.

tof_tools.h
Author(s):
Christophe Christophe hugon.nosp@m.@cen.nosp@m.bg.in.nosp@m.2p3..nosp@m.fr
Sophie Blondel blond.nosp@m.el@l.nosp@m.al.in.nosp@m.2p3..nosp@m.fr
Francois Mauger mauge.nosp@m.r@lp.nosp@m.ccaen.nosp@m..in2.nosp@m.p3.fr
Arnaud Chapon chapo.nosp@m.n@lp.nosp@m.ccaen.nosp@m..in2.nosp@m.p3.fr

Creation date: 2010-03-01
Last modified: 2012-03-03

Description:
Utilities for computing TOF related values.
May be used by "2e" "1e1g" ... specialized TOF algorithms.

---

Member Function Documentation

double nemo3::tof_tools::Beta	(	double	ke_,
		double	mass_
	)		[private]

internal method to get the relativistic beta factor for an energy ke_ and a mass mass_

Returns:

\( \beta=\frac { \sqrt{E.(E+2m)}} {E+m} \)

double nemo3::tof_tools::ECorrTracking	(	double	energy_,
		double	trlen_,
		scin_hit_id &	id_
	)		[private]

correct the energy of a particle

The correction is based on T. Filipova's note 1999 nemoa.car FUNCTION TK_ENERGY(IT) (not well understood). In the goal to be more accurate, a new correction was developped and not yet implemented in tof_tools, but has confirm the result of Fillipova with non significant difference on the final result.

for internal and external walls:

\( \Delta E = c \times length + \frac { a1 - a3 \times ( length - a2 )^2 } {E} + \frac { h1 \times E \times h1 \times E } { 1. + E / h2 } \)

with

\( c = 0.475 \)
\( h1 = 0.145 \times 10^{-5} \)
\( h2 = 6490. \)
\( a1 = 5630. \)
\( a2 = 134. \)
\( a3 = 0.404 \)

for top and bottom walls :

\( \Delta E = c0 + c \times length + \frac { a1 + a2 \times length } {E} + \frac { h1^2 \times E^2} { 1. + E / h2 } \)

with

\( c = 0.326 \)
\( h1 = 0.2 \times 10^{-5} \)
\( h2 = 4660. \)
\( a1 = 1800. \)
\( a2 = 27. \)
\( c0 = 15.8 \)

bool nemo3::tof_tools::get_chi2	(	const track &	track1_,
		const track &	track2_,
		double &	internal_chi2_,
		double &	external_chi2_,
		bool	keep_dt_ = false
	)

Calculate the chi2 between two electrons for a given dt.

keep_dt_ means keep last tof_tools::get_dt calculation result, or redo it.

In summary, it calculate dt^2/sum (sigma^2). With \( t_{thn} \) the theoritics time of tracks n in the hypothesis (internal or external) :

\( \sigma_{th}^2 = { (\frac {t_{th1} \times kMe^2} {E1 \times (E1 + kMe) \times (E1 + 2.kMe)} })^2 \times ( \sigma E ( E1 ))^2 + \frac {\sigma_{Trlen}^2 (kMe) } { ( \beta^2 (E1, kMe) \times kC )} + \sigma_T^2 ( id1, E1 ) +\\ { (\frac {t_{th2} \times kMe^2} {E2 \times (E2 + kMe) \times (E2 + 2.kMe)} })^2 \times ( \sigma E ( E2 ))^2 + \frac {\sigma_{Trlen}^2 (kMe) } { ( \beta^2 (E2, kMe) \times kC )} + \sigma_T^2 ( id2, E2 ) \)

\( \sigma_{xp}^2 = tse^2(id1) + ltce^2(id1) + ltfluct^2(id1)\\ + tse^2(id2) + ltce^2(id2) + ltfluct^2(id2) \)

See also:

SigmaT

get_tse

get_ltce

get_ltfluct

SigmaTrlen

SigmaE

kMe

bool nemo3::tof_tools::get_chi2	(	const track &	track_,
		const scin_hit &	scin_hit_,
		double &	internal_chi2_,
		double &	external_chi2_,
		bool	keep_dt_ = false,
		bool	change_elec_energy_ = false,
		double	elec_energy_ = 0,
		double	elec_length_ = 0
	)

Calculate the chi2 between an electron and a gamma for a given dt.

keep_dt_ means keep last tof_tools::get_dt calculation result, or redo it.

In summary, it calculate dt^2/sum (sigma^2). With \( t_{thn} \) the theoritics time of track and scin n in the hypothesis (internal or external) :

\( \sigma_{th}^2 = { (\frac {t_{th1} \times kMe^2} {E1 \times (E1 + kMe) \times (E1 + 2.kMe)} })^2 \times ( \sigma E ( E1 ))^2 + \frac {\sigma_{Trlen}^2 (kMe) } { ( \beta^2 (E1, kMe) \times kC )} + \sigma_T^2 ( id1, E1 ) +\\ \frac {\sigma_{Trlen}^2 (0) } { ( \beta^2 (E2, 0) \times kC )} + \sigma_T^2 ( id2, E2 ) \)

\( \sigma_{xp}^2 = tse^2(id1) + ltce^2(id1) + ltfluct^2(id1)\\ + tse^2(id2) + ltce^2(id2) + ltfluct^2(id2) \)

See also:

SigmaT

get_tse

get_ltce

get_ltfluct

SigmaTrlen

SigmaE

kMe

bool nemo3::tof_tools::get_chi2	(	const scin_hit &	scin_hit1_,
		const scin_hit &	scin_hit2_,
		double &	chi2_,
		bool	keep_dt_ = false
	)

Calculate the chi2 between two gammas scin to scin for a given dt.

keep_dt_ means keep last tof_tools::get_dt calculation result, or redo it.

In summary, it calculate dt^2/sum (sigma^2). With \( t_{thn} \) the theoritics time of scins n in the hypothesis (from 1 to 2) :

\( \sigma_{th}^2 = \frac {\sigma_{Trlen}^2 (0) } { ( \beta^2 (E1, 0) \times kC )} + \sigma_T^2 ( id1, E1 ) +\ \ \frac {\sigma_{Trlen}^2 (0) } { ( \beta^2 (E2, 0) \times kC )} + \sigma_T^2 ( id2, E2 ) \)

\( \sigma_{xp}^2 = tse^2(id1) + ltce^2(id1) + ltfluct^2(id1)\\ + tse^2(id2) + ltce^2(id2) + ltfluct^2(id2) \)

See also:

SigmaT

get_tse

get_ltce

get_ltfluct

SigmaTrlen

bool nemo3::tof_tools::get_chi2_1e	(	const scin_hit &	scin_hit1_,
		const scin_hit &	scin_hit2_,
		double &	internal_chi2_,
		double &	internal_prob_
	)

Calculate the chi2 for one electron scin to scin for a given times.

In summary, it calculate dt^2/sum (sigma^2). With sigmas:

See also:

for measured dt:

SigmaT

get_tse

get_ltce

get_ltfluct

for theoretics:

SigmaTrlen

Only the internal hypthesis is tested. Returns true if chi2 if good.

bool nemo3::tof_tools::get_chi2_2e_1g	(	const track &	track1_,
		const track &	track2_,
		const scin_hit &	scin_hit3_,
		const bool	switch_,
		double &	internal_chi2_,
		double &	internal_prob_
	)

Calculate the chi2 between two electrons and a gamma for given times.

In summary, it calculate dt^2/sum (sigma^2). With sigmas:

See also:

for measured dt:

SigmaT

get_tse

get_ltce

get_ltfluct

for theoretics:

SigmaTrlen

Only the internal hypthesis is tested. Returns true if chi2 if good.

bool nemo3::tof_tools::get_chi2_2e_2g	(	const track &	track1_,
		const track &	track2_,
		const scin_hit &	scin_hit3_,
		const scin_hit &	scin_hit4_,
		const bool	switch_,
		double &	internal_chi2_,
		double &	internal_prob_
	)

Calculate the chi2 between two electrons and two gammas for given times.

In summary, it calculate dt^2/sum (sigma^2). With sigmas:

See also:

for measured dt:

SigmaT

get_tse

get_ltce

get_ltfluct

for theoretics:

SigmaTrlen

Only the internal hypthesis is tested. Returns true if chi2 if good.

bool nemo3::tof_tools::get_chi2_2g	(	const track &	track_,
		const scin_hit &	scin_hit2_,
		const scin_hit &	scin_hit3_,
		const bool	switch_,
		double &	internal_chi2_,
		double &	internal_prob_,
		bool	change_elec_energy_ = false,
		double	elec_energy_ = 0,
		double	elec_length_ = 0
	)

Calculate the chi2 between one electron and two gammas for given times.

change_elec_energy_ means that it takes the elec_energy_ instead of the energy of the associated scin, and the elec_length_ to calculate energy losses.

In summary, it calculate dt^2/sum (sigma^2). With sigmas:

See also:

for measured dt:

SigmaT

get_tse

get_ltce

get_ltfluct

for theoretics:

SigmaTrlen

Only the internal hypthesis is tested. Returns true if chi2 if good.

bool nemo3::tof_tools::get_chi2_3g	(	const track &	track_,
		const scin_hit &	scin_hit2_,
		const scin_hit &	scin_hit3_,
		const scin_hit &	scin_hit4_,
		const bool	switch_,
		double &	internal_chi2_,
		double &	internal_prob_,
		bool	change_elec_energy_ = false,
		double	elec_energy_ = 0,
		double	elec_length_ = 0
	)

Calculate the chi2 between one electron and tree gammas for given times.

change_elec_energy_ means that it takes the elec_energy_ instead of the energy of the associated scin, and the elec_length_ to calculate energy losses.

In summary, it calculate dt^2/sum (sigma^2). With sigmas:

See also:

for measured dt:

SigmaT

get_tse

get_ltce

get_ltfluct

for theoretics:

SigmaTrlen

Only the internal hypthesis is tested. Returns true if chi2 if good.

bool nemo3::tof_tools::get_dt	(	const track &	track1_,
		const track &	track2_,
		double &	dt_int_,
		double &	dt_ext_
	)

get time difference between theoretics and measured ToF of two electrons.

calculate the internal and external Theoretics time of flight based on tof_tools::ECorrTracking for energy, tof_tools::T_th for time.
It makes the difference with associated scins of track1 and 2 times in internal and external hypothesis. More the dt_int or dt_ext are close to 0, more the hypothesis seems to be true.

Returns:

true if the condition a correct (track::is_prompt, track::has_associated_scin, track::has_vertex and track::has_length)

bool nemo3::tof_tools::get_dt	(	const track &	track1_,
		const scin_hit &	scin_hit2_,
		double &	dt_int_,
		double &	dt_ext_,
		bool	change_elec_energy_ = false,
		double	elec_energy_ = 0,
		double	elec_length_ = 0
	)

get time difference between theoretics and measured ToF of an electron and a gamma.

calculate the internal and external Theoretics time of flight based on tof_tools::ECorrTracking for energy, tof_tools::T_th for time.
It makes the difference with associated scins of track1 and scin2 times in internal and external hypothesis. More the dt_int or dt_ext are close to 0, more the hypothesis seems to be true.

Returns:

true if the condition a correct (track::is_prompt, track::has_associated_scin, track::has_vertex and track::has_length, different PMs for electron and gamma)

bool nemo3::tof_tools::get_dt	(	const scin_hit &	scin_hit1_,
		const scin_hit &	scin_hit2_,
		double &	dt_
	)

get time difference between theoretics and measured ToF of two gamma.

This element is special, and done for gamma tracking. It do not consider a vertex, the hypothesis is between the two scintillators. The center of the scintillators are the start and stop points. It calculate the Theoretics time of flight based on tof_tools::T_th for time.
Then t makes the difference with associated scins of scin1 and 2 times for 1 to 2 hypothesis. More the dt_int or dt_ext are close to 0, more the hypothesis seems to be true.

Returns:

true if the condition a correct (track::is_prompt, track::has_associated_scin, track::has_vertex and track::has_length, different PMs for electron and gamma)

static void nemo3::tof_tools::get_proba	(	double	internal_chi2_,
		double	external_chi2_,
		double &	internal_prob_,
		double &	external_prob_,
		unsigned int	freedom_ = 1
	)		[static]

Get probability for freedom_ degree of freedom.

it uses the gsl function gsl_cdf_chisq_Q:
\(p(x) dx = {1 \over 2 \Gamma(\nu/2) } (x/2)^{\nu/2 - 1} \exp(-x/2) dx\)

double nemo3::tof_tools::SigmaE	(	scin_hit_id &	id_,
		double	ke_
	)		[private]

sigma from laser measurement

It is based on laser FWHM from N3Db for each PM, and energy of the particle

\( \sigma E = 1000. \times \text{FWHM (PM)} \times \frac {\sqrt { 0.001 * E }} {kSig} \)

See also:

FWHM

kSig

double nemo3::tof_tools::SigmaT	(	scin_hit_id &	id_,
		double	ke_,
		bool	gamma_ = false
	)		[private]

Total transition time error.

dependant of kTaus, fwhm_trans, kVg FWHM and energy

\( \sigma T = \sqrt { \frac { kTauSc^2 + kTauEl^2 + fwhm_{trans}^2 / kSig^2 } { E \times (kSig / \text{FWHM (PM)})^2 } \times ( 1. + kVg ) } \)

See also:

FWHM

kSig

kTauSc

kTauSc_g

kTauEl

fwhm_trans

kVg

double nemo3::tof_tools::T_th	(	double	ke_,
		double	mass_,
		double	trlen_
	)		[private]

internal method to get the theoretics time of flight

I calculate the ToF of a particle of mass mass_ and energy ke_ on a length trlengj_ in cm.

Returns:

\( \frac {length} {\beta (E, m) \times c} \)

See also:

Beta

kC

---

The documentation for this class was generated from the following file:

• include/N3AnaBase/measurements/tof_tools.h